Curated Shelf

Biology

Darwin's Origin, Huxley — popular-level Victorian/Edwardian science writing.

1490 WorksDrawn from Project Gutenberg Bookshelf #669

Pharmacographia A history of the principal drugs of vegetable origin, met with in Great Britain and British India
Flückiger, Friedrich A. (Friedrich August) & Hanbury, Daniel
23,506 Gutenberg downloadsen2022Difficulty 66 (Academic)
Origin of Cultivated Plants The International Scientific Series Volume XLVIII
Candolle, Alphonse de
19,376 Gutenberg downloadsen2014Difficulty 62 (Academic)
Studies of American Fungi. Mushrooms, Edible, Poisonous, etc.
Atkinson, George Francis
15,601 Gutenberg downloadsen2008Difficulty 50 (College)
The Natural History of Pliny, Volume 5 (of 6)
Pliny, the Elder
14,594 Gutenberg downloadsen2019Difficulty 50 (College)
Vegetable Teratology An Account of the Principal Deviations from the Usual Construction of Plants
Masters, Maxwell T. (Maxwell Tylden)
12,313 Gutenberg downloadsen2007Difficulty 61 (Academic)
The Elements of Bacteriological Technique A Laboratory Guide for Medical, Dental, and Technical Students. Second Edition Rewritten and Enlarged.
Eyre, J. W. H. (John William Henry)
12,051 Gutenberg downloadsen2009Difficulty 59 (Graduate)
Life and Letters of Charles Darwin — Volume 1
Darwin, Charles
11,685 Gutenberg downloadsen2000Difficulty 54 (Graduate)
More Letters of Charles Darwin — Volume 1 A Record of His Work in a Series of Hitherto Unpublished Letters
Darwin, Charles
11,476 Gutenberg downloadsen2001Difficulty 50 (College)
On the Origin of Species By Means of Natural Selection Or, the Preservation of Favoured Races in the Struggle for Life
Darwin, Charles
11,346 Gutenberg downloadsen1998Difficulty 61 (Academic)
The Variation of Animals and Plants Under Domestication, Vol. I.
Darwin, Charles
10,500 Gutenberg downloadsen2008Difficulty 67 (Academic)
The Natural History of Pliny, Volume 3 (of 6)
Pliny, the Elder
10,021 Gutenberg downloadsen2019Difficulty 38 (High School)
On Growth and Form
Thompson, D'Arcy Wentworth
9,996 Gutenberg downloadsen2017Difficulty 53 (Graduate)
Darwin, and After Darwin, Volumes 1 and 3 An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions
Romanes, George John
8,952 Gutenberg downloadsen2008Difficulty 55 (Graduate)
On the Origin of Species by Means of Natural Selection or the Preservation of Favoured Races in the Struggle for Life. (2nd edition)
Darwin, Charles
8,719 Gutenberg downloadsen2007Difficulty 73 (Expert)
The Notebooks of Leonardo Da Vinci — Complete
Leonardo, da Vinci
8,505 Gutenberg downloadsen2004Difficulty 52 (Graduate)
The Animal Parasites of Man
Fantham, Harold Benjamin & Braun, Max & Stephens, J. W. W. (John William Watson) & Theobald, Fred. V. (Frederick Vincent)
8,063 Gutenberg downloadsen2018Difficulty 67 (Academic)
The Variation of Animals and Plants under Domestication
Darwin, Charles
8,052 Gutenberg downloadsen2002Difficulty 86 (Specialist)
Mysteries of Bee-keeping Explained
Quinby, M. (Moses)
7,998 Gutenberg downloadsen2008Difficulty 78 (Expert)
Evolution, Old & New Or, the Theories of Buffon, Dr. Erasmus Darwin and Lamarck, as compared with that of Charles Darwin
Butler, Samuel
7,988 Gutenberg downloadsen2007Difficulty 57 (Graduate)
The Evolution of Marriage and of the Family
Letourneau, Ch. (Charles)
7,954 Gutenberg downloadsen2022Difficulty 61 (Academic)
An introduction to the study of mammals living and extinct
Flower, William Henry & Lydekker, Richard
7,705 Gutenberg downloadsen2025Difficulty 77 (Expert)
Letters of Asa Gray; Vol. 2
Gray, Asa
7,574 Gutenberg downloadsen2017Difficulty 47 (College)
Contributions to the Theory of Natural Selection A Series of Essays
Wallace, Alfred Russel
7,552 Gutenberg downloadsen2007Difficulty 63 (Academic)
Cattle and Their Diseases Embracing Their History and Breeds, Crossing and Breeding, and Feeding and Management; with the Diseases to Which They Are Subject, and the Remedies Best Adapted to Their Cure
Jennings, Robert
7,482 Gutenberg downloadsen2007Difficulty 67 (Academic)
Fossil plants, Vol. 2 : $b A text-book for students of botany and geology
Seward, A. C. (Albert Charles)
7,172 Gutenberg downloadsen2022Difficulty 63 (Academic)
Travels in Peru and India While Superintending the Collection of Chinchona Plants and Seeds in South America, and Their Introduction into India.
Markham, Clements R. (Clements Robert), Sir
6,643 Gutenberg downloadsen2017Difficulty 62 (Academic)
Manual of the Trees of North America (Exclusive of Mexico) 2nd ed.
Sargent, Charles Sprague
6,446 Gutenberg downloadsen2014Difficulty 78 (Expert)
Lichens
Smith, Annie Lorrain
6,287 Gutenberg downloadsen2020Difficulty 52 (Graduate)
The Cambridge natural history, Vol. 02 (of 10)
Beddard, Frank E. (Frank Evers) & Benham, W. B. (William Blaxland) & Gamble, F. W. (Frederick William) & Hartog, Marcus & Sheldon, Lilian
6,268 Gutenberg downloadsen2023Difficulty 74 (Expert)
The Foundations of the Origin of Species Two Essays written in 1842 and 1844
Darwin, Charles
6,188 Gutenberg downloadsen2007Difficulty 56 (Graduate)
Birds of the Rockies
Keyser, Leander S. (Leander Sylvester)
6,174 Gutenberg downloadsen2008Difficulty 58 (Graduate)
Insects and Diseases A Popular Account of the Way in Which Insects may Spread or Cause some of our Common Diseases
Doane, Rennie Wilbur
6,041 Gutenberg downloadsen2009Difficulty 58 (Graduate)
The Cambridge natural history, Vol. 01 (of 10)
Hartog, Marcus & Hickson, Sydney J. (Sydney John) & MacBride, E. W. (Ernest William) & Sollas, Igerna Brünhilda Johnson
6,020 Gutenberg downloadsen2023Difficulty 71 (Expert)
A Manual of Philippine Birds
McGregor, Richard C. (Richard Crittenden)
5,852 Gutenberg downloadsen2014Difficulty 68 (Academic)
The Cambridge natural history, Vol. 03 (of 10)
Cooke, A. H. (Alfred Hands) & Reed, F. R. C. (Frederick Richard Cowper)
5,819 Gutenberg downloadsen2023Difficulty 63 (Academic)
Evolution in Modern Thought
Unknown
5,764 Gutenberg downloadsen2007Difficulty 73 (Expert)
The Medicinal Plants of the Philippines
Pardo de Tavera, T. H. (Trinidad Hermenegildo)
5,417 Gutenberg downloadsen2008Difficulty 67 (Academic)
Handbook of Birmingham Prepared for the Members of the British Association, 1886
British Association for the Advancement of Science
5,355 Gutenberg downloadsen2015Difficulty 51 (Graduate)
The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality
Schmid, Rudolf
5,278 Gutenberg downloadsen2007Difficulty 56 (Graduate)
A History of North American Birds; Land Birds; Vol. 3 of 3
Baird, Spencer Fullerton & Brewer, T. M. (Thomas Mayo) & Ridgway, Robert
5,046 Gutenberg downloadsen2017Difficulty 59 (Graduate)
Sketches of the Natural History of Ceylon
Tennent, James Emerson, Sir
5,038 Gutenberg downloadsen2004Difficulty 72 (Expert)
Makers of British Botany; a collection of biographies by living botanists
Unknown
5,030 Gutenberg downloadsen2014Difficulty 61 (Academic)
A Text-book of Entomology Including the Anatomy, Physiology, Embryology and Metamorphoses of Insects for Use in Agricultural and Technical Schools and Colleges as Well as by the Working Entomologist
Packard, A. S. (Alpheus Spring)
4,985 Gutenberg downloadsen2021Difficulty 63 (Academic)
Zoölogische Philosophie Of beschouwingen over de Natuurlijke Historie der dieren etc.
Lamarck, Jean Baptiste Pierre Antoine de Monet de
4,734 Gutenberg downloadsnl2008
The Dawn of Reason; or, Mental Traits in the Lower Animals
Weir, James, Jr.
4,644 Gutenberg downloadsen2007Difficulty 70 (Academic)
Sir Jagadis Chunder Bose, His Life and Speeches
Bose, Jagadis Chandra
4,588 Gutenberg downloadsen2007Difficulty 65 (Academic)
An Introduction to Entomology: Vol. 3 or Elements of the Natural History of the Insects
Kirby, William & Spence, William
4,582 Gutenberg downloadsen2013Difficulty 61 (Academic)
The works of Francis Maitland Balfour, Volume 2 (of 4) : $b A treatise on comparative embryology: Invertebrata
Balfour, Francis M. (Francis Maitland)
4,572 Gutenberg downloadsen2014Difficulty 64 (Academic)
The Stock-Feeder's Manual the chemistry of food in relation to the breeding and feeding of live stock
Cameron, Charles Alexander, Sir
4,554 Gutenberg downloadsen2008Difficulty 59 (Graduate)
The Cambridge natural history, Vol. 07 (of 10)
Boulenger, George Albert & Bridge, T. W. (Thomas William) & Herdman, W. A. (William Abbott), Sir
4,527 Gutenberg downloadsen2024Difficulty 76 (Expert)
Cassell's Natural History, Vol. 1 (of 6)
Unknown
4,403 Gutenberg downloadsen2017Difficulty 94 (Quantum Electrodynamics)
The Insect World Being a Popular Account of the Orders of Insects; Together with a Description of the Habits and Economy of Some of the Most Interesting Species
Figuier, Louis
4,323 Gutenberg downloadsen2014Difficulty 55 (Graduate)
Outlines of Dairy Bacteriology, 8th edition A Concise Manual for the Use of Students in Dairying
Russell, H. L. (Harry Luman)
4,320 Gutenberg downloadsen2009Difficulty 62 (Academic)
An Introduction to Entomology: Vol. 4 or Elements of the Natural History of the Insects
Kirby, William & Spence, William
4,297 Gutenberg downloadsen2013Difficulty 68 (Academic)
Fossil plants, Vol. 3 : $b A text-book for students of botany and geology
Seward, A. C. (Albert Charles)
4,247 Gutenberg downloadsen2025Difficulty 64 (Academic)
The Microscope. Its History, Construction, and Application 15th ed. Being a familiar introduction to the use of the instrument, and the study of microscopical science
Hogg, Jabez
4,220 Gutenberg downloadsen2020Difficulty 67 (Academic)
Fossil plants, Vol. 1 : $b [A text-book] for students of botany and geology
Seward, A. C. (Albert Charles)
4,191 Gutenberg downloadsen2022Difficulty 57 (Graduate)
The Expression of the Emotions in Man and Animals
Darwin, Charles
4,163 Gutenberg downloadsen1998Difficulty 64 (Academic)
The reason why : $b a careful collection of many hundreds of reasons for things which, though generally believed, are imperfectly understood. A book of condensed scientific knowledge for the million
Philp, Robert Kemp
4,106 Gutenberg downloadsen2014Difficulty 86 (Specialist)
The Origin of Species by Means of Natural Selection Or, the Preservation of Favoured Races in the Struggle for Life, 6th Edition
Darwin, Charles
4,068 Gutenberg downloadsen1999Difficulty 65 (Academic)
The Cambridge natural history, Vol. 04 (of 10)
Smith, Geoffrey & Thompson, D'Arcy Wentworth & Warburton, Cecil & Weldon, Walter Frank Raphael & Woods, Henry
4,063 Gutenberg downloadsen2023Difficulty 72 (Expert)
Delineations of the Ox Tribe: The Natural History of Bulls, Bisons, and Buffaloes. Exhibiting all the Known Species and the More Remarkable Varieties of the Genus Bos.
Vasey, George
3,962 Gutenberg downloadsen2009Difficulty 57 (Graduate)
The Cambridge natural history, Vol. 06 (of 10)
Sharp, David
3,909 Gutenberg downloadsen2023Difficulty 65 (Academic)
Man And His Ancestor: A Study In Evolution
Morris, Charles
3,908 Gutenberg downloadsen2009Difficulty 58 (Graduate)
Aristotle's History of Animals In Ten Books
Aristotle
3,892 Gutenberg downloadsen2019Difficulty 55 (Graduate)
The life of Jean Henri Fabre, the entomologist, 1823-1910
Fabre, Augustin
3,884 Gutenberg downloadsen2024Difficulty 58 (Graduate)
The book of wonders : $b gives plain and simple answers to the thousands of everyday questions that are asked and which all should be able to, but cannot answer...
Unknown
3,849 Gutenberg downloadsen2025Difficulty 48 (College)
First course in biology
Bailey, L. H. (Liberty Hyde) & Coleman, Walter Moore
3,831 Gutenberg downloadsen2025Difficulty 46 (College)
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, First Part: Porulosa (Spumellaria and Acantharia) Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76, Vol. XVIII
Haeckel, Ernst
3,823 Gutenberg downloadsen2013Difficulty 64 (Academic)
The Voyage of the Beagle
Darwin, Charles
3,738 Gutenberg downloadsen1997Difficulty 56 (Graduate)
Species Plantarum, Sections IV-V
Linné, Carl von
3,670 Gutenberg downloadsla2008
History of Botany (1530-1860)
Sachs, Julius
3,609 Gutenberg downloadsen2020Difficulty 72 (Expert)
The grapes of New York
Hedrick, U. P.
3,530 Gutenberg downloadsen2014Difficulty 63 (Academic)
Darwin
Bradford, Gamaliel
3,503 Gutenberg downloadsen2023Difficulty 60 (Graduate)
Journal of Researches into the Natural History and Geology of the Countries Visited During the Voyage Round the World of H.M.S. Beagle Under the Command of Captain Fitz Roy, R.N.
Darwin, Charles
3,494 Gutenberg downloadsen2003Difficulty 66 (Academic)
Snakes: Curiosities and Wonders of Serpent Life
Hopley, Catherine Cooper
3,486 Gutenberg downloadsen2016Difficulty 56 (Graduate)
An Elementary Study of Insects
Haseman, Leonard
3,449 Gutenberg downloadsen2007Difficulty 51 (Graduate)
The works of Francis Maitland Balfour, Volume 3 (of 4) : $b A treatise on comparative embryology: Vertebrata
Balfour, Francis M. (Francis Maitland)
3,422 Gutenberg downloadsen2014Difficulty 54 (Graduate)
The Sea and Its Living Wonders A Popular Account of the Marvels of the Deep and of the Progress of Martime Discovery from the Earliest Ages to the Present Time
Hartwig, G. (Georg)
3,396 Gutenberg downloadsen2020Difficulty 62 (Academic)
Himalayan Journals — Complete Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.
Hooker, Joseph Dalton
3,393 Gutenberg downloadsen2004Difficulty 99 (Quantum Electrodynamics)
A handbook of systematic botany
Warming, Eugenius
3,386 Gutenberg downloadsen2022Difficulty 55 (Graduate)
Encyclopaedia Britannica, 11th Edition, "Foraminifera" to "Fox, Edward" Volume 10, Slice 6
Various
3,248 Gutenberg downloadsen2011Difficulty 67 (Academic)
Herbal Simples Approved for Modern Uses of Cure
Fernie, William Thomas
3,219 Gutenberg downloadsen2006Difficulty 54 (Graduate)
Are the Effects of Use and Disuse Inherited? An Examination of the View Held by Spencer and Darwin
Ball, W. P. (William Platt)
3,182 Gutenberg downloadsen2008Difficulty 68 (Academic)
Freedom in Science and Teaching. from the German of Ernst Haeckel
Haeckel, Ernst
3,158 Gutenberg downloadsen2008Difficulty 73 (Expert)
Life and Matter: A Criticism of Professor Haeckel's "Riddle of the Universe"
Lodge, Oliver, Sir
3,115 Gutenberg downloadsen2008Difficulty 75 (Expert)
The Biotic Associations of Cockroaches
Roth, Louis M. (Louis Marcus) & Willis, Edwin R.
3,073 Gutenberg downloadsen2014Difficulty 71 (Expert)
The Evolution of Man
Haeckel, Ernst
3,056 Gutenberg downloadsen2005Difficulty 49 (College)
Rollo's Experiments
Abbott, Jacob
3,055 Gutenberg downloadsen2008Difficulty 35 (High School)
Toadstools, mushrooms, fungi, edible and poisonous; one thousand American fungi How to select and cook the edible; how to distinguish and avoid the poisonous, with full botanic descriptions. Toadstool poisons and their treatment, instructions to students, recipes for cooking, etc., etc.
McIlvaine, Charles & Macadam, Robert K.
3,004 Gutenberg downloadsen2016Difficulty 54 (Graduate)
Flora of the Sudan
Broun, A. F. (Alfred Forbes) & Massey, R. E. (Reginald Ernest)
3,001 Gutenberg downloadsen2025Difficulty 50 (College)
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, Second Part: Subclass Osculosa; Index Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76, Vol. XVIII
Haeckel, Ernst
2,995 Gutenberg downloadsen2013Difficulty 65 (Academic)
Venoms: Venomous Animals and Antivenomous Serum-therapeutics
Calmette, A. (Albert)
2,991 Gutenberg downloadsen2016Difficulty 56 (Graduate)
Eleanor Ormerod, LL. D., Economic Entomologist : Autobiography and Correspondence
Ormerod, Eleanor A. (Eleanor Anne)
2,976 Gutenberg downloadsen2020Difficulty 76 (Expert)
The flowering plants of Africa An analytical key to the genera of African phanerograms
Thonner, Franz
2,947 Gutenberg downloadsen2022Difficulty 57 (Graduate)
Reptiles and Birds A Popular Account of Their Various Orders, With a Description of the Habits and Economy of the Most Interesting
Figuier, Louis
2,929 Gutenberg downloadsen2014Difficulty 79 (Expert)
The Organism as a Whole, from a Physicochemical Viewpoint
Loeb, Jacques
2,920 Gutenberg downloadsen2014Difficulty 68 (Academic)
Cassell's Natural History, Vol. 3 (of 6)
Unknown
2,902 Gutenberg downloadsen2020Difficulty 100 (Quantum Electrodynamics)
A Guide to the Study of Fishes, Volume 2 (of 2)
Jordan, David Starr
2,884 Gutenberg downloadsen2016Difficulty 83 (Specialist)
Form and Function: A Contribution to the History of Animal Morphology
Russell, E. S. (Edward Stuart)
2,859 Gutenberg downloadsen2007Difficulty 59 (Graduate)
Letters of Asa Gray; Vol. 1
Gray, Asa
2,839 Gutenberg downloadsen2017Difficulty 49 (College)
The Cambridge natural history, Vol. 05 (of 10)
Sedgwick, Adam & Sharp, David & Sinclair, F. G. (Frederick Granville)
2,838 Gutenberg downloadsen2023Difficulty 66 (Academic)
Cassell's Natural History, Vol. 2 (of 6)
Unknown
2,825 Gutenberg downloadsen2019Difficulty 99 (Quantum Electrodynamics)
A text-book of veterinary anatomy
Sisson, Septimus
2,818 Gutenberg downloadsen2025Difficulty 76 (Expert)
The Natural History of the Varieties of Man
Latham, R. G. (Robert Gordon)
2,815 Gutenberg downloadsen2014Difficulty 64 (Academic)
Encyclopaedia Britannica, 11th Edition, "Echinoderma" to "Edward, prince of Wales" Volume 8, Slice 10
Various
2,755 Gutenberg downloadsen2011Difficulty 65 (Academic)
The Naturalist on the River Amazons
Bates, Henry Walter
2,715 Gutenberg downloadsen2000Difficulty 67 (Academic)
The Nursery-Book: A Complete Guide to the Multiplication and Pollination of Plants
Bailey, L. H. (Liberty Hyde)
2,665 Gutenberg downloadsen2015Difficulty 50 (College)
Everyday Objects; Or, Picturesque Aspects of Natural History.
Adams, W. H. Davenport (William Henry Davenport)
2,611 Gutenberg downloadsen2014Difficulty 57 (Graduate)
A History of North American Birds; Land Birds; Vol. 2 of 3
Baird, Spencer Fullerton & Brewer, T. M. (Thomas Mayo) & Ridgway, Robert
2,589 Gutenberg downloadsen2017Difficulty 46 (College)
The Descent of Man, and Selection in Relation to Sex
Darwin, Charles
2,588 Gutenberg downloadsen2000Difficulty 69 (Academic)
The Cambridge natural history, Vol. 08 (of 10)
Gadow, Hans
2,576 Gutenberg downloadsen2024Difficulty 63 (Academic)
At the Deathbed of Darwinism: A Series of Papers
Dennert, Eberhard
2,573 Gutenberg downloadsen2007Difficulty 68 (Academic)
Charles Darwin: His Life Told in an Autobiographical Chapter, and in a Selected Series of His Published Letters
Darwin, Charles
2,564 Gutenberg downloadsen2012Difficulty 53 (Graduate)
Anatomy of the Cat
Reighard, Jacob & Jennings, H. S. (Herbert Spencer)
2,483 Gutenberg downloadsen2018Difficulty 52 (Graduate)
Woman in Science With an Introductory Chapter on Woman's Long Struggle for Things of the Mind
Zahm, J. A. (John Augustine)
2,470 Gutenberg downloadsen2011Difficulty 66 (Academic)
The Principles of Biology, Volume 1 (of 2)
Spencer, Herbert
2,438 Gutenberg downloadsen2017Difficulty 63 (Academic)
The plums of New York
Hedrick, U. P.
2,437 Gutenberg downloadsen2024Difficulty 65 (Academic)
Life histories of North American shore birds, Part 1 (of 2)
Bent, Arthur Cleveland
2,432 Gutenberg downloadsen2014Difficulty 62 (Academic)
The Works of William Harvey M.D. Translated from the Latin with a life of the author
Harvey, William
2,429 Gutenberg downloadsen2019Difficulty 66 (Academic)
Explanation of Terms Used in Entomology
Smith, John Bernhard
2,388 Gutenberg downloadsen2007Difficulty 57 (Graduate)
The pears of New York
Hedrick, U. P.
2,370 Gutenberg downloadsen2014Difficulty 58 (Graduate)
Philosophical transactions, Vol. L. Part I. For the year 1757. Giving some account of the present undertakings, studies, and labours, of the ingenious, in many considerable parts of the world.
Various & Royal Society (Great Britain)
2,365 Gutenberg downloadsen2021Difficulty 49 (College)
Darwinism (1889) An exposition of the theory of natural selection, with some of its applications
Wallace, Alfred Russel
2,362 Gutenberg downloadsen2005Difficulty 82 (Specialist)
Galen: On the Natural Faculties
Galen
2,352 Gutenberg downloadsen2013Difficulty 65 (Academic)
The Taleef Shereef; Or, Indian Materia Medica
Unknown
2,347 Gutenberg downloadsen2016Difficulty 54 (Graduate)
Scurvy, Past and Present
Hess, Alfred F.
2,346 Gutenberg downloadsen2012Difficulty 62 (Academic)
The Geological History of Plants
Dawson, John William, Sir
2,341 Gutenberg downloadsen2016Difficulty 55 (Graduate)
Cave Hunting Researches on the evidence of caves respecting the early inhabitants of Europe
Dawkins, William Boyd
2,317 Gutenberg downloadsen2016Difficulty 77 (Expert)
The Book of the Pearl The history, art, science, and industry of the queen of gems
Kunz, George Frederick & Stevenson, Charles Hugh
2,297 Gutenberg downloadsen2020Difficulty 64 (Academic)
Biographies of distinguished scientific men. First series
Arago, F. (François)
2,290 Gutenberg downloadsen2005Difficulty 52 (Graduate)
The Descent of Man and Selection in Relation to Sex, Vol. II (1st Edition)
Darwin, Charles
2,281 Gutenberg downloadsen2011Difficulty 59 (Graduate)
The Ocean World: Being a Description of the Sea and Its Living Inhabitants.
Figuier, Louis
2,271 Gutenberg downloadsen2014Difficulty 56 (Graduate)
The Sea-beach at Ebb-tide A Guide to the Study of the Seaweeds and the Lower Animal Life Found Between Tide-marks
Arnold, Augusta Foote
2,261 Gutenberg downloadsen2013Difficulty 57 (Graduate)
Observations of a Naturalist in the Pacific Between 1896 and 1899, Volume 2 Plant-Dispersal
Guppy, H. B. (Henry Brougham)
2,257 Gutenberg downloadsen2017Difficulty 59 (Graduate)
The Geographical Distribution of Animals, Volume 2 With a study of the relations of living and extinct faunas as elucidating the past changes of the Earth's surface
Wallace, Alfred Russel
2,241 Gutenberg downloadsen2018Difficulty 64 (Academic)
A History of North American Birds; Land Birds; Vol. 1 of 3
Baird, Spencer Fullerton & Brewer, T. M. (Thomas Mayo) & Ridgway, Robert
2,228 Gutenberg downloadsen2017Difficulty 66 (Academic)
The Birds of Australia, Vol. 4 of 7
Gould, John
2,224 Gutenberg downloadsen2019Difficulty 64 (Academic)
Alfred Russel Wallace: Letters and Reminiscences, Vol. 1
Wallace, Alfred Russel & Marchant, James, Sir
2,214 Gutenberg downloadsen2005Difficulty 65 (Academic)
The Cambridge natural history, Vol. 09 (of 10)
Evans, A. H. (Arthur Humble)
2,213 Gutenberg downloadsen2024Difficulty 59 (Graduate)
Encyclopaedia Britannica, 11th Edition, "Matter" to "Mecklenburg" Volume 17, Slice 8
Various
2,210 Gutenberg downloadsen2013Difficulty 71 (Expert)
Animal Life and Intelligence
Morgan, C. Lloyd (Conwy Lloyd)
2,200 Gutenberg downloadsen2015Difficulty 57 (Graduate)
Encyclopaedia Britannica, 11th Edition, "Ichthyology" to "Independence" Volume 14, Slice 3
Various
2,188 Gutenberg downloadsen2012Difficulty 67 (Academic)
Mental Evolution in Man: Origin of Human Faculty
Romanes, George John
2,185 Gutenberg downloadsen2015Difficulty 68 (Academic)
Insect Architecture
Rennie, James
2,180 Gutenberg downloadsen2014Difficulty 50 (College)
The Prolongation of Life: Optimistic Studies
Metchnikoff, Elie
2,169 Gutenberg downloadsen2016Difficulty 58 (Graduate)
Narrative of the Circumnavigation of the Globe by the Austrian Frigate Novara, Volume II (Commodore B. Von Wullerstorf-Urbair,) Undertaken by Order of the Imperial Government in the Years 1857, 1858, & 1859, Under the Immediate Auspices of His I. and R. Highness the Archduke Ferdinand Maximilian, Commander-In-Chief of the Austrian Navy.
Scherzer, Karl, Ritter von
2,168 Gutenberg downloadsen2012Difficulty 56 (Graduate)
The Story-book of Science
Fabre, Jean-Henri
2,156 Gutenberg downloadsen2018Difficulty 43 (College)
Australian insects
Froggatt, Walter W. (Walter Wilson)
2,150 Gutenberg downloadsen2025Difficulty 52 (Graduate)
The Coal Measures Amphibia of North America
Moodie, Roy Lee
2,146 Gutenberg downloadsen2019Difficulty 62 (Academic)
Tobacco; Its History, Varieties, Culture, Manufacture and Commerce
Billings, E. R.
2,145 Gutenberg downloadsen2008Difficulty 59 (Graduate)
Histology of medicinal plants
Mansfield, William James
2,142 Gutenberg downloadsen2021Difficulty 70 (Academic)
Fungi: Their Nature and Uses
Cooke, M. C. (Mordecai Cubitt)
2,136 Gutenberg downloadsen2009Difficulty 57 (Graduate)
Parasites: A Treatise on the Entozoa of Man and Animals Including Some Account of the Ectozoa
Cobbold, T. Spencer (Thomas Spencer)
2,129 Gutenberg downloadsen2014Difficulty 60 (Graduate)
Prof. Koch's Method to Cure Tuberculosis Popularly Treated
Birnbaum, Max
2,124 Gutenberg downloadsen2008Difficulty 59 (Graduate)
Elementary Botany
Atkinson, George Francis
2,111 Gutenberg downloadsen2021Difficulty 53 (Graduate)
Philosophical transactions, Vol. L. Part II. For the year 1758. Giving some account of the present undertakings, studies, and labours, of the ingenious, in many considerable parts of the world.
Various & Royal Society (Great Britain)
2,110 Gutenberg downloadsen2022Difficulty 49 (College)
Fabre's Book of Insects
Fabre, Jean-Henri
2,107 Gutenberg downloadsen2021Difficulty 43 (College)
Essays Upon Heredity and Kindred Biological Problems Authorised Translation
Weismann, August
2,105 Gutenberg downloadsen2015Difficulty 58 (Graduate)
A Guide to the Study of Fishes, Volume 1 (of 2)
Jordan, David Starr
2,104 Gutenberg downloadsen2014Difficulty 66 (Academic)
The Variation of Animals and Plants Under Domestication, Volume II (of 2)
Darwin, Charles
2,055 Gutenberg downloadsen2009Difficulty 73 (Expert)
Biology and Its Makers With Portraits and Other Illustrations
Locy, William A. (William Albert)
2,046 Gutenberg downloadsen2019Difficulty 56 (Graduate)
The Romance of Plant Life Interesting Descriptions of the Strange and Curious in the Plant World
Elliot, G. F. Scott (George Francis Scott)
2,019 Gutenberg downloadsen2014Difficulty 71 (Expert)
The Tropical World Aspects of man and nature in the equatorial regions of the globe.
Hartwig, G. (Georg)
2,000 Gutenberg downloadsen2020Difficulty 95 (Quantum Electrodynamics)
The Harvest of the Sea A contribution to the natural and economic history of the British food fishes
Bertram, James Glass
1,992 Gutenberg downloadsen2020Difficulty 66 (Academic)
The Journal of a Disappointed Man
Barbellion, W. N. P.
1,991 Gutenberg downloadsen2012Difficulty 42 (College)
Studies in the Theory of Descent, Volume I
Weismann, August
1,985 Gutenberg downloadsen2015Difficulty 68 (Academic)
The Progress of the Century
Unknown
1,976 Gutenberg downloadsen2017Difficulty 69 (Academic)
A Journey in Brazil
Agassiz, Louis & Agassiz, Elizabeth Cabot Cary
1,970 Gutenberg downloadsen2017Difficulty 55 (Graduate)
The Genus Pinus
Shaw, George Russell
1,956 Gutenberg downloadsen2008Difficulty 58 (Graduate)
The Principles of Biology, Volume 2 (of 2)
Spencer, Herbert
1,950 Gutenberg downloadsen2022Difficulty 63 (Academic)
Plants Poisonous to Live Stock
Long, Harold Cecil
1,946 Gutenberg downloadsen2020Difficulty 60 (Graduate)
On Molecular and Microscopic Science, Volume 2 (of 2)
Somerville, Mary
1,929 Gutenberg downloadsen2018Difficulty 58 (Graduate)
The Descent of Man and Selection in Relation to Sex, Vol. I
Darwin, Charles
1,917 Gutenberg downloadsen2011Difficulty 65 (Academic)
The Outline of Science, Vol. 1 (of 4) A Plain Story Simply Told
Thomson, J. Arthur (John Arthur)
1,915 Gutenberg downloadsen2007Difficulty 66 (Academic)
British Pomology Or, the History, Description, Classification, and Synonymes, of the Fruits and Fruit Trees of Great Britain
Hogg, Robert
1,878 Gutenberg downloadsen2014Difficulty 58 (Graduate)
The Cambridge natural history, Vol. 10 (of 10)
Beddard, Frank E. (Frank Evers)
1,875 Gutenberg downloadsen2012Difficulty 61 (Academic)
Cassell's book of birds; vol. 4
Brehm, Alfred Edmund
1,867 Gutenberg downloadsen2022Difficulty 58 (Graduate)
How to Use the Popular Science Library; History of Science; General Index
Serviss, Garrett Putman & Selwyn-Brown, Arthur
1,863 Gutenberg downloadsen2016Difficulty 64 (Academic)
An essay towards a natural history of serpents
Owen, Charles
1,860 Gutenberg downloadsen2023Difficulty 49 (College)
New Zealand Moths and Butterflies (Macro-Lepidoptera)
Hudson, G. V. (George Vernon)
1,857 Gutenberg downloadsen2013Difficulty 60 (Graduate)
The Dog
Youatt, William
1,854 Gutenberg downloadsen2005Difficulty 60 (Graduate)
Animal Locomotion; or, walking, swimming, and flying With a dissertation on aëronautics
Pettigrew, James Bell
1,840 Gutenberg downloadsen2018Difficulty 66 (Academic)
A treatise on the origin, progress, prevention, and cure of dry rot in timber : $b with remarks on the means of preserving wood from destruction by sea worms, beetles, ants, etc.
Britton, Thomas Allen
1,820 Gutenberg downloadsen2017Difficulty 57 (Graduate)
Proceedings of the California Academy of Sciences, Volume III, 1863-1867
Various
1,803 Gutenberg downloadsen2020Difficulty 58 (Graduate)
An introduction to the study of fishes
Günther, Albert C. L. G. (Albert Carl Ludwig Gotthilf)
1,800 Gutenberg downloadsen2023Difficulty 74 (Expert)
Problems of Genetics
Bateson, William
1,771 Gutenberg downloadsen2014Difficulty 65 (Academic)
On the Genesis of Species
Mivart, St. George Jackson
1,766 Gutenberg downloadsen2007Difficulty 63 (Academic)
The Life of the Grasshopper
Fabre, Jean-Henri
1,751 Gutenberg downloadsen2021Difficulty 51 (Graduate)
Applied Eugenics
Popenoe, Paul & Johnson, Roswell H. (Roswell Hill)
1,749 Gutenberg downloadsen2006Difficulty 55 (Graduate)
Travels into North America, Volume 3 (of 3)
Kalm, Pehr
1,748 Gutenberg downloadsen2024Difficulty 50 (College)
A history of land mammals in the western hemisphere
Scott, William Berryman
1,744 Gutenberg downloadsen2025Difficulty 66 (Academic)
Life and Letters of Charles Darwin — Volume 2
Darwin, Charles
1,728 Gutenberg downloadsen2000Difficulty 53 (Graduate)
Nature's Teachings: Human Invention Anticipated by Nature
Wood, J. G. (John George)
1,722 Gutenberg downloadsen2016Difficulty 51 (Graduate)
Science from an Easy Chair
Lankester, E. Ray (Edwin Ray), Sir
1,721 Gutenberg downloadsen2018Difficulty 52 (Graduate)
Identification of the Larger Fungi
Watling, Roy
1,718 Gutenberg downloadsen2019Difficulty 62 (Academic)
The Structure and Life-history of the Cockroach (Periplaneta orientalis) An Introduction to the Study of Insects
Miall, L. C. (Louis Compton) & Denny, Alfred
1,715 Gutenberg downloadsen2016Difficulty 58 (Graduate)
Evolution and Adaptation
Morgan, Thomas Hunt
1,709 Gutenberg downloadsen2020Difficulty 62 (Academic)
Essays on the Microscope Containing a Practical Description of the Most Improved Microscopes, a General History of Insects, etc., etc.
Adams, George
1,707 Gutenberg downloadsen2020Difficulty 62 (Academic)
Studies in the History and Method of Science, vol. 1 (of 2)
Unknown
1,698 Gutenberg downloadsen2014Difficulty 57 (Graduate)
Memoirs of the Distinguished Men of Science of Great Britain Living in the Years 1807-8
Walker, William
1,688 Gutenberg downloadsen2018Difficulty 61 (Academic)
The Evolution Theory, Vol. 1 of 2
Weismann, August
1,687 Gutenberg downloadsen2021Difficulty 59 (Graduate)
Micrographia Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses with Observations and Inquiries Thereupon
Hooke, Robert
1,669 Gutenberg downloadsen2005Difficulty 76 (Expert)
The life of Pasteur
Vallery-Radot, René
1,663 Gutenberg downloadsen2019Difficulty 59 (Graduate)
The romance of natural history, second series
Gosse, Philip Henry
1,643 Gutenberg downloadsen2010Difficulty 76 (Expert)
The cherries of New York
Hedrick, U. P.
1,639 Gutenberg downloadsen2014Difficulty 67 (Academic)
The romance of insect life : $b Interesting descriptions of the strange and curious in the insect world
Selous, Edmund
1,634 Gutenberg downloadsen2023Difficulty 76 (Expert)
The Plants of Michigan Simple Keys for the Identification of the Native Seed Plants of the State
Gleason, Henry A. (Henry Allan)
1,630 Gutenberg downloadsen2010Difficulty 45 (College)
Initiative in Evolution
Kidd, Walter
1,621 Gutenberg downloadsen2016Difficulty 57 (Graduate)
Forest Trees of Texas: How to Know Them
Mattoon, Wilbur R. (Wilbur Reed) & Webster, C. B. (Cyril Bertram)
1,620 Gutenberg downloadsen2016Difficulty 56 (Graduate)
Birds from North Borneo University of Kansas Publications, Museum of Natural History, Volume 17, No. 8, pp. 377-433, October 27, 1966
Thompson, Max C.
1,619 Gutenberg downloadsen2010Difficulty 56 (Graduate)
The Life and Love of the Insect
Fabre, Jean-Henri
1,617 Gutenberg downloadsen2022Difficulty 50 (College)
Argentine Ornithology, Volume 1 (of 2) A descriptive catalogue of the birds of the Argentine Republic.
Sclater, Philip Lutley & Hudson, W. H. (William Henry)
1,610 Gutenberg downloadsen2012Difficulty 62 (Academic)
Lamarck, the Founder of Evolution: His Life and Work
Packard, A. S. (Alpheus Spring)
1,610 Gutenberg downloadsen2007Difficulty 58 (Graduate)
Herbals, Their Origin and Evolution: A Chapter in the History of Botany 1470-1670
Arber, Agnes Robertson
1,581 Gutenberg downloadsen2014Difficulty 55 (Graduate)
A Natural History for Young People: Our Animal Friends in Their Native Homes including mammals, birds and fishes
Humphreys, Phebe Westcott
1,548 Gutenberg downloadsen2015Difficulty 63 (Academic)
Handbook of Medical Entomology
Riley, William A. (William Albert) & Johannsen, O. A. (Oskar Augustus)
1,540 Gutenberg downloadsen2010Difficulty 57 (Graduate)
The winners in life's race : $b Or, the great backboned family
Buckley, Arabella B. (Arabella Burton)
1,538 Gutenberg downloadsen2024Difficulty 63 (Academic)
Text book of veterinary medicine, Volume 3 (of 5)
Law, James
1,535 Gutenberg downloadsen2023Difficulty 63 (Academic)
The birds of Jamaica
Gosse, Philip Henry
1,528 Gutenberg downloadsen2024Difficulty 63 (Academic)
Mammals of Washington, Volume 2 University of Kansas Publications Museum of Natural History
Dalquest, Walter Woelber
1,520 Gutenberg downloadsen2016Difficulty 52 (Graduate)
Beginners' zoology
Coleman, Walter Moore
1,517 Gutenberg downloadsen2024Difficulty 46 (College)
Life and death
Dastre, A. (Albert)
1,513 Gutenberg downloadsen2021Difficulty 56 (Graduate)
Zoonomia; Or, the Laws of Organic Life, Vol. I
Darwin, Erasmus
1,504 Gutenberg downloadsen2005Difficulty 64 (Academic)
The Origin of Man and of His Superstitions
Read, Carveth
1,502 Gutenberg downloadsen2014Difficulty 59 (Graduate)
Life histories of North American woodpeckers
Bent, Arthur Cleveland
1,475 Gutenberg downloadsen2024Difficulty 65 (Academic)
An Introduction to Nature-study
Stenhouse, E. (Ernest)
1,466 Gutenberg downloadsen2020Difficulty 42 (College)
Darwin and Modern Science
Seward, A. C. (Albert Charles)
1,463 Gutenberg downloadsen1999Difficulty 56 (Graduate)
New-England's rarities discovered : $b In birds, beasts, fishes, serpents, and plants of that country
Josselyn, John, active 1630-1675
1,463 Gutenberg downloadsen2023Difficulty 57 (Graduate)
Journal of a tour in Marocco and the Great Atlas
Hooker, Joseph Dalton & Ball, John
1,462 Gutenberg downloadsen2023Difficulty 66 (Academic)
History of the Conflict Between Religion and Science
Draper, John William
1,454 Gutenberg downloadsen1998Difficulty 62 (Academic)
The Pleistocene of North America and its vertebrated animals from the states east of the Mississippi River and from the Canadian provinces east of longitude 95°
Hay, Oliver Perry
1,451 Gutenberg downloadsen2020Difficulty 73 (Expert)
A Civic Biology, Presented in Problems
Hunter, George W. (George William)
1,450 Gutenberg downloadsen2012Difficulty 56 (Graduate)
The Malay Archipelago, Volume 1 The Land of the Orang-utan and the Bird of Paradise; A Narrative of Travel, with Studies of Man and Nature
Wallace, Alfred Russel
1,445 Gutenberg downloadsen2001Difficulty 63 (Academic)
The Insect
Michelet, Jules
1,443 Gutenberg downloadsen2013Difficulty 61 (Academic)
More Letters of Charles Darwin — Volume 2 A Record of His Work in a Series of Hitherto Unpublished Letters
Darwin, Charles
1,442 Gutenberg downloadsen2001Difficulty 50 (College)
Cosmos: A Sketch of the Physical Description of the Universe, Vol. 1
Humboldt, Alexander von
1,439 Gutenberg downloadsen2005Difficulty 67 (Academic)
Botany for Ladies or, A Popular Introduction to the Natural System of Plants, According to the Classification of De Candolle.
Loudon, Mrs. (Jane)
1,437 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Ornithological biography, Vol. 4 (of 5) : $b An account of the habits of the birds of the United States of America
Audubon, John James
1,435 Gutenberg downloadsen2023Difficulty 62 (Academic)
Encyclopaedia Britannica, 11th Edition, "Joints" to "Justinian I." Volume 15, Slice 5
Various
1,431 Gutenberg downloadsen2012Difficulty 65 (Academic)
The Hunting Wasps
Fabre, Jean-Henri
1,426 Gutenberg downloadsen2022Difficulty 57 (Graduate)
Elementary Zoology, Second Edition
Kellogg, Vernon L. (Vernon Lyman)
1,425 Gutenberg downloadsen2012Difficulty 57 (Graduate)
Philosophical Transactions of the Royal Society - Vol 1 - 1666 Giving some Accompt of the present Undertakings, Studies, and Labours of the Ingenious in many considerable parts of the World
Various
1,420 Gutenberg downloadsen2009Difficulty 58 (Graduate)
Text book of veterinary medicine, Volume 4 (of 5)
Law, James
1,415 Gutenberg downloadsen2024Difficulty 69 (Academic)
The plurality of the human race
Pouchet, G. (Georges)
1,413 Gutenberg downloadsen2023Difficulty 61 (Academic)
Langstroth on the Hive and the Honey-Bee: A Bee Keeper's Manual
Langstroth, L. L. (Lorenzo Lorraine)
1,410 Gutenberg downloadsen2008Difficulty 44 (College)
The Arctic World : $b Its plants, animals, and natural phenomena. With a historical sketch of Arctic discovery, down to the British polar expedition: 1875-76.
Anonymous
1,408 Gutenberg downloadsen2023Difficulty 60 (Graduate)
Useful Knowledge: Volume 2. Vegetables Or, a familiar account of the various productions of nature
Bingley, William
1,400 Gutenberg downloadsen2018Difficulty 51 (Graduate)
Manual of the apiary
Cook, Albert John
1,395 Gutenberg downloadsen2022Difficulty 49 (College)
More Beetles
Fabre, Jean-Henri
1,393 Gutenberg downloadsen2022Difficulty 47 (College)
Structure and Functions of the Body A Hand-Book of Anatomy and Physiology for Nurses and Others Desiring a Practical Knowledge of the Subject
Fiske, Annette
1,393 Gutenberg downloadsen2021Difficulty 66 (Academic)
An Introduction to Entomology: Vol. 1 or Elements of the Natural History of the Insects
Kirby, William & Spence, William
1,389 Gutenberg downloadsen2013Difficulty 74 (Expert)
The Life of the Spider
Fabre, Jean-Henri
1,386 Gutenberg downloadsen1999Difficulty 52 (Graduate)
Domestic Animals History and description of the horse, mule, cattle, sheep, swine, poultry and farm dogs; with directions for their management, breeding, crossing, rearing, feeding, and preparation for a profitable market; also their diseases and remedies. Together with full directions for the management of the dairy.
Allen, Richard Lamb
1,384 Gutenberg downloadsen2010Difficulty 72 (Expert)
Extinct Monsters A Popular Account of Some of the Larger Forms of Ancient Animal Life
Hutchinson, H. N. (Henry Neville)
1,372 Gutenberg downloadsen2013Difficulty 53 (Graduate)
Anthropoid apes
Hartmann, Robert
1,371 Gutenberg downloadsen2025Difficulty 53 (Graduate)
The Life of the Caterpillar
Fabre, Jean-Henri
1,369 Gutenberg downloadsen2021Difficulty 51 (Graduate)
The Autobiography of Charles Darwin
Darwin, Charles
1,365 Gutenberg downloadsen1999Difficulty 53 (Graduate)
Bass, Pike, Perch, and Others
Henshall, James A. (James Alexander)
1,349 Gutenberg downloadsen2012Difficulty 57 (Graduate)
The Life of the Scorpion
Fabre, Jean-Henri
1,335 Gutenberg downloadsen2021Difficulty 49 (College)
Coral Reefs
Darwin, Charles
1,332 Gutenberg downloadsen2001Difficulty 57 (Graduate)
The heart of Africa, Vol. 1 (of 2)
Schweinfurth, Georg August
1,332 Gutenberg downloadsen2023Difficulty 81 (Specialist)
Regeneration
Morgan, Thomas Hunt
1,328 Gutenberg downloadsen2018Difficulty 57 (Graduate)
The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science
Nicholson, Henry Alleyne
1,319 Gutenberg downloadsen2004Difficulty 76 (Expert)
André Michaux's Travels into Kentucky, 1793-96; François André Michaux's Travels West of Alleghany Mountains, 1802; Thaddeus Mason Harris's Journal of a Tour Northwest of Alleghany Mountains, 1803.
Michaux, André & Harris, Thaddeus Mason & Michaux, François André
1,318 Gutenberg downloadsen2025Difficulty 65 (Academic)
Botany: The Science of Plant Life
Taylor, Norman
1,314 Gutenberg downloadsen2015Difficulty 56 (Graduate)
Bacteria Especially as they are related to the economy of nature, to industrial processes, and to the public health
Newman, George, Sir
1,312 Gutenberg downloadsen2015Difficulty 66 (Academic)
The Sacred Beetle, and Others
Fabre, Jean-Henri
1,309 Gutenberg downloadsen2021Difficulty 56 (Graduate)
Alfred Russel Wallace: Letters and Reminiscences, Vol. 2
Wallace, Alfred Russel & Marchant, James, Sir
1,307 Gutenberg downloadsen2005Difficulty 69 (Academic)
Travels into North America, Volume 2 (of 3)
Kalm, Pehr
1,307 Gutenberg downloadsen2023Difficulty 47 (College)
Animal Parasites and Messmates
Beneden, P. J. van (Pierre Joseph)
1,305 Gutenberg downloadsen2015Difficulty 57 (Graduate)
The Life and Letters of George John Romanes, M.A., LL.D., F.R.S.
Romanes, George John & Romanes, Ethel Duncan
1,304 Gutenberg downloadsen2015Difficulty 52 (Graduate)
Insectivorous Plants
Darwin, Charles
1,298 Gutenberg downloadsen2004Difficulty 63 (Academic)
Zoölogy: The Science of Animal Life Popular Science Library, Volume XII (of 16), P. F. Collier & Son Company, 1922
Ingersoll, Ernest
1,297 Gutenberg downloadsen2015Difficulty 63 (Academic)
Cassell's book of birds; vol. 3
Brehm, Alfred Edmund
1,294 Gutenberg downloadsen2019Difficulty 62 (Academic)
Autobiography and Selected Essays
Huxley, Thomas Henry
1,286 Gutenberg downloadsen2006Difficulty 54 (Graduate)
The Birds of Washington (Volume 1 of 2) A complete, scientific and popular account of the 372 species of birds found in the state
Dawson, William Leon & Bowles, John Hooper
1,277 Gutenberg downloadsen2014Difficulty 58 (Graduate)
General Science
Clark, Bertha May
1,276 Gutenberg downloadsen2005Difficulty 53 (Graduate)
The ivory king : $b A popular history of the elephant and its allies
Holder, Charles Frederick
1,269 Gutenberg downloadsen2021Difficulty 54 (Graduate)
A century of science in America : $b with special reference to the American Journal of Science, 1818-1918
Unknown
1,267 Gutenberg downloadsen2024Difficulty 60 (Graduate)
A Hand-book to the Primates, Volume 1 (of 2)
Forbes, Henry O. (Henry Ogg)
1,263 Gutenberg downloadsen2013Difficulty 56 (Graduate)
The Power of Movement in Plants
Darwin, Charles & Darwin, Francis, Sir
1,263 Gutenberg downloadsen2004Difficulty 70 (Academic)
Catalogue of Economic Plants in the Collection of the U. S. Department of Agriculture
Saunders, William
1,259 Gutenberg downloadsen2008Difficulty 52 (Graduate)
The Moths of the British Isles, First Series Comprising the Families Sphingidæ to Noctuidæ
South, Richard
1,259 Gutenberg downloadsen2013Difficulty 54 (Graduate)
A Treatise on the Plague and Yellow Fever With an Appendix, containing histories of the plague at Athens in the time of the Peloponnesian War; at Constantinople in the time of Justinian; at London in 1665; at Marseilles in 1720
Tytler, James
1,257 Gutenberg downloadsen2022Difficulty 55 (Graduate)
Mammals of Mesa Verde National Park, Colorado
Anderson, Sydney
1,257 Gutenberg downloadsen2010Difficulty 53 (Graduate)
The Life of the Fly; With Which are Interspersed Some Chapters of Autobiography
Fabre, Jean-Henri
1,255 Gutenberg downloadsen2002Difficulty 54 (Graduate)
Garden Pests in New Zealand A Popular Manual for Practical Gardeners, Farmers and Schools
Miller, David
1,253 Gutenberg downloadsen2014Difficulty 71 (Expert)
Birds useful and birds harmful
Herman, Ottó & Owen, J. A. (Jean Allan)
1,244 Gutenberg downloadsen2016Difficulty 56 (Graduate)
An Introduction to Entomology: Vol. 2 or Elements of the Natural History of the Insects
Kirby, William & Spence, William
1,243 Gutenberg downloadsen2013Difficulty 61 (Academic)
Illustrations of Exotic Entomology, Volume 1
Drury, Dru
1,242 Gutenberg downloadsen2014Difficulty 62 (Academic)
Clever Hans (The Horse of Mr. Von Osten) A contribution to experimental animal and human psychology
Pfungst, Oskar
1,241 Gutenberg downloadsen2010Difficulty 57 (Graduate)
Luck, or Cunning, as the Main Means of Organic Modification
Butler, Samuel
1,239 Gutenberg downloadsen2004Difficulty 61 (Academic)
Glimpses of Ocean Life; Or, Rock-Pools and the Lessons they Teach
Harper, John
1,238 Gutenberg downloadsen2016Difficulty 66 (Academic)
Life and Letters of Thomas Henry Huxley — Volume 3
Huxley, Thomas Henry
1,237 Gutenberg downloadsen2004Difficulty 58 (Graduate)
Bodily changes in pain, hunger, fear, and rage : $b an account of recent researches into the function of emotional excitement
Cannon, Walter B. (Walter Bradford)
1,235 Gutenberg downloadsen2024Difficulty 75 (Expert)
Studies in the Theory of Descent, Volume II
Weismann, August
1,235 Gutenberg downloadsen2015Difficulty 65 (Academic)
A system of practical medicine. By American authors. Vol. 1 : $b Pathology and general diseases
Unknown
1,230 Gutenberg downloadsen2012Difficulty 63 (Academic)
The Industries of Animals
Houssay, Frédéric
1,230 Gutenberg downloadsen2009Difficulty 64 (Academic)
Pearls & Parasites
Shipley, A. E. (Arthur Everett), Sir
1,228 Gutenberg downloadsen2016Difficulty 55 (Graduate)
A first book in organic evolution
Shute, D. Kerfoot (Daniel Kerfoot)
1,227 Gutenberg downloadsen2024Difficulty 58 (Graduate)
Sex-linked Inheritance in Drosophila
Morgan, Thomas Hunt & Bridges, Calvin B. (Calvin Blackman)
1,227 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Butterflies and Moths (British)
Furneaux, William S.
1,225 Gutenberg downloadsen2010Difficulty 44 (College)
The Formation of Vegetable Mould Through the Action of Worms With Observations on Their Habits
Darwin, Charles
1,217 Gutenberg downloadsen2000Difficulty 63 (Academic)
Outlines of Creation
Noyce, Elisha
1,216 Gutenberg downloadsen2015Difficulty 68 (Academic)
The Life of the Weevil
Fabre, Jean-Henri & Teixeira de Mattos, Alexander
1,213 Gutenberg downloadsen2021Difficulty 49 (College)
Life's Dawn on Earth Being the history of the oldest known fossil remains, and their relations to geological time and to the development of the animal kingdom
Dawson, John William, Sir
1,212 Gutenberg downloadsen2015Difficulty 58 (Graduate)
Island Life; Or, The Phenomena and Causes of Insular Faunas and Floras
Wallace, Alfred Russel
1,211 Gutenberg downloadsen2010Difficulty 89 (Specialist)
Wild Flowers An Aid to Knowledge of Our Wild Flowers and Their Insect Visitors
Blanchan, Neltje
1,210 Gutenberg downloadsen2002Difficulty 58 (Graduate)
The Romance of the Microscope An interesting description of its uses in all branches of science, industry, agriculture, and in the detection of crime, with a short account of its origin, history, and development
Ealand, C. A. (Charles Aubrey)
1,206 Gutenberg downloadsen2015Difficulty 55 (Graduate)
The Bird Book Illustrating in natural colors more than seven hundred North American birds; also several hundred photographs of their nests and eggs.
Reed, Chester A. (Chester Albert)
1,202 Gutenberg downloadsen2009Difficulty 47 (College)
Lay Sermons, Addresses and Reviews
Huxley, Thomas Henry
1,198 Gutenberg downloadsen2005Difficulty 65 (Academic)
The apiary; or, bees, bee-hives, and bee culture [1878] being a familiar account of the habits of bees, and the most improved methods of management
Neighbor, Alfred
1,198 Gutenberg downloadsen2022Difficulty 53 (Graduate)
The Principal Species of Wood: Their Characteristic Properties First Edition
Snow, Charles H. (Charles Henry)
1,196 Gutenberg downloadsen2014Difficulty 60 (Graduate)
Mr. Ray's travels, Vol. 2 : $b A collection of curious travels and voyages. Containing Dr Leonhart Rauwolf's journey into the eastern countries, viz. Syria, Palestine, or the Holy Land, Armenia, Mesopotamia, Assyria, Chaldea, &c., translated from the Original High Dutch, by Nicholas Staphorst. And also, travels into Greece, Asia minor, Egypt, Arabia felix, Petræa, Ethiopia, the Red Sea, &c. Collected from the observations of Mons. Belon, Prosper Alpinus, Dr. Huntington, Mr. Vernon, Sir George Wheeler, Dr. Smith, Mr. Greaves, and others. To which are added three catalogues of such trees, shrubs, and herbs, as grow in the Levant. By the Rev. John Ray, F.R.S.
Ray, John & Rauwolf, Leonhard
1,192 Gutenberg downloadsen2025Difficulty 57 (Graduate)
Thomas Henry Huxley; A Sketch Of His Life And Work
Mitchell, P. Chalmers (Peter Chalmers), Sir
1,192 Gutenberg downloadsen2005Difficulty 68 (Academic)
An Examination of Weismannism
Romanes, George John
1,188 Gutenberg downloadsen2015Difficulty 74 (Expert)
The Science of Fingerprints: Classification and Uses
United States. Federal Bureau of Investigation
1,188 Gutenberg downloadsen2006Difficulty 61 (Academic)
Flowers of mountain and plain
Clements, Edith S. (Edith Schwartz)
1,186 Gutenberg downloadsen2014Difficulty 50 (College)
Trees of Indiana First Revised Edition (Publication No. 13, Department of Conservation, State of Indiana)
Deam, Charles Clemon
1,184 Gutenberg downloadsen2012Difficulty 50 (College)
The Evolution Theory, Vol. 2 of 2
Weismann, August
1,183 Gutenberg downloadsen2021Difficulty 64 (Academic)
Field, Forest and Farm Things interesting to young nature-lovers, including some matters of moment to gardeners and fruit-growers
Fabre, Jean-Henri
1,169 Gutenberg downloadsen2022Difficulty 54 (Graduate)
The Vertebrate Skeleton
Reynolds, Sidney H. (Sidney Hugh)
1,168 Gutenberg downloadsen2013Difficulty 64 (Academic)
Argentine Ornithology, Volume 2 (of 2) A descriptive catalogue of the birds of the Argentine Republic.
Sclater, Philip Lutley & Hudson, W. H. (William Henry)
1,151 Gutenberg downloadsen2012Difficulty 56 (Graduate)
Evidence as to Man's Place in Nature
Huxley, Thomas Henry
1,150 Gutenberg downloadsen2001Difficulty 56 (Graduate)
The works of Francis Maitland Balfour, Volume 1 (of 4) : $b Separate memoirs
Balfour, Francis M. (Francis Maitland)
1,150 Gutenberg downloadsen2012Difficulty 58 (Graduate)
The Life of the Bee
Maeterlinck, Maurice
1,149 Gutenberg downloadsen2003Difficulty 60 (Graduate)
The Beaked Whales of the Family Ziphiidae An Account of the Beaked Whales of the Family Ziphiidae in the Collection of the United States Museum...
True, Frederick W. (Frederick William)
1,145 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Special report on diseases of cattle
United States. Bureau of Animal Industry & Atkinson, V. T. (Vickers T.) & Dickson, Dr. (William) & Eichhorn, A. (Adolph) & Hickman, Richard W. (Richard West) & Law, James & Lowe, (Dr.) (William Herbert) & Marsh, C. Dwight (Charles Dwight) & Mohler, John R. (John Robbins) & Murray, A. J. (Alexander James) & Pearson, Leonard & Ransom, Brayton Howard & Trumbower, M. R. (Milton R.) & Woodward, Dr. (Benjamin Tilghman)
1,144 Gutenberg downloadsen2009Difficulty 53 (Graduate)
Parallel Paths: A Study in Biology, Ethics, and Art
Rolleston, T. W. (Thomas William)
1,137 Gutenberg downloadsen2014Difficulty 69 (Academic)
Insect life: Souvenirs of a naturalist
Fabre, Jean-Henri
1,136 Gutenberg downloadsen2022Difficulty 51 (Graduate)
An Australian Bird Book: A Pocket Book for Field Use
Leach, John Albert
1,134 Gutenberg downloadsen2010Difficulty 51 (Graduate)
Intelligence in Plants and Animals Being a New Edition of the Author's Privately Issued "Soul and Immortality."
Gentry, Thomas G. (Thomas George)
1,132 Gutenberg downloadsen2021Difficulty 71 (Expert)
The Nature of Animal Light
Harvey, E. Newton (Edmund Newton)
1,131 Gutenberg downloadsen2010Difficulty 71 (Expert)
Text book of veterinary medicine, Volume 1 (of 5)
Law, James
1,129 Gutenberg downloadsen2023Difficulty 67 (Academic)
Cassell's book of birds; vol. 1
Brehm, Alfred Edmund
1,127 Gutenberg downloadsen2015Difficulty 61 (Academic)
The Wild Elephant and the Method of Capturing and Taming it in Ceylon
Tennent, James Emerson, Sir
1,120 Gutenberg downloadsen2018Difficulty 65 (Academic)
A History of Science — Volume 2
Williams, Henry Smith & Williams, Edward Huntington
1,114 Gutenberg downloadsen1999Difficulty 63 (Academic)
The Chain of Life in Geological Time A Sketch of the Origin and Succession of Animals and Plants
Dawson, John William, Sir
1,114 Gutenberg downloadsen2011Difficulty 56 (Graduate)
The History of Creation, Vol. 2 (of 2) Or the Development of the Earth and its Inhabitants by the Action of Natural Causes
Haeckel, Ernst
1,109 Gutenberg downloadsen2012Difficulty 61 (Academic)
An Introduction to the History of Science
Libby, Walter
1,106 Gutenberg downloadsen2012Difficulty 62 (Academic)
The useful trees of northern Nigeria
Lely, Hugh Vandervaes
1,104 Gutenberg downloadsen2023Difficulty 56 (Graduate)
The Honey-Bee: Its Natural History, Physiology and Management
Bevan, Edward
1,096 Gutenberg downloadsen2022Difficulty 63 (Academic)
The Natural History of the Tea-Tree, with Observations on the Medical Qualities of Tea, and on the Effects of Tea-Drinking
Lettsom, John Coakley
1,096 Gutenberg downloadsen2021Difficulty 52 (Graduate)
Proserpina, Volume 1 Studies of Wayside Flowers, While the Air was Yet Pure Among the Alps and in the Scotland and England Which My Father Knew
Ruskin, John
1,095 Gutenberg downloadsen2007Difficulty 52 (Graduate)
A treatise on the esculent funguses of England containing an account of their classical history, uses, characters, development, structure, nutritious properties, modes of cooking and preserving, etc.
Badham, David
1,092 Gutenberg downloadsen2019Difficulty 68 (Academic)
The Glow-Worm and Other Beetles
Fabre, Jean-Henri
1,092 Gutenberg downloadsen2009Difficulty 50 (College)
Collected Essays, Volume V Science and Christian Tradition: Essays
Huxley, Thomas Henry
1,091 Gutenberg downloadsen2005Difficulty 64 (Academic)
Irritability : $b a physiological analysis of the general effect of stimuli in living substance
Verworn, Max
1,090 Gutenberg downloadsen2021Difficulty 65 (Academic)
North American Recent Soft-Shelled Turtles (Family Trionychidae)
Webb, Robert G. (Robert Gravem)
1,081 Gutenberg downloadsen2012Difficulty 71 (Expert)
Scientific American magazine Vol 2. No. 3 Oct 10 1846 The Advocate of Industry and Journal of Scientific, Mechanical and Other Improvements
Various
1,079 Gutenberg downloadsen2009Difficulty 49 (College)
The Minds and Manners of Wild Animals: A Book of Personal Observations
Hornaday, William T. (William Temple)
1,075 Gutenberg downloadsen2004Difficulty 56 (Graduate)
Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 1
Humboldt, Alexander von & Bonpland, Aimé
1,074 Gutenberg downloadsen2004Difficulty 55 (Graduate)
On the mode of communication of cholera
Snow, John
1,073 Gutenberg downloadsen2024Difficulty 58 (Graduate)
Reflections on the Decline of Science in England, and on Some of Its Causes
Babbage, Charles
1,073 Gutenberg downloadsen1998Difficulty 63 (Academic)
The Crayfish: An Introduction to the Study of Zoology.
Huxley, Thomas Henry
1,073 Gutenberg downloadsen2019Difficulty 54 (Graduate)
Man, Past and Present
Keane, A. H. (Augustus Henry)
1,072 Gutenberg downloadsen2011Difficulty 60 (Graduate)
Social Life in the Insect World
Fabre, Jean-Henri
1,069 Gutenberg downloadsen2006Difficulty 49 (College)
Taboo and genetics : $b A study of the biological, sociological and psychological foundation of the family
Knight, Melvin M. (Melvin Moses) & Blanchard, Phyllis & Peters, Iva Lowther
1,065 Gutenberg downloadsen2004Difficulty 61 (Academic)
Appletons' Popular Science Monthly, December 1899 Vol. LVI, November, 1899 to April, 1900
Various
1,064 Gutenberg downloadsen2014Difficulty 72 (Expert)
The book of antelopes, vol. 1 (of 4)
Sclater, Philip Lutley & Thomas, Oldfield
1,057 Gutenberg downloadsen2023Difficulty 49 (College)
Essays Upon Some Controverted Questions
Huxley, Thomas Henry
1,056 Gutenberg downloadsen2010Difficulty 78 (Expert)
Life Movements in Plants, Volume I
Bose, Jagadis Chandra
1,056 Gutenberg downloadsen2015Difficulty 69 (Academic)
Buffon's Natural History. Volume 06 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
Buffon, Georges Louis Leclerc, comte de
1,053 Gutenberg downloadsen2014Difficulty 60 (Graduate)
The Butterflies of the British Isles
South, Richard
1,051 Gutenberg downloadsen2013Difficulty 57 (Graduate)
Unconscious Memory
Butler, Samuel
1,050 Gutenberg downloadsen2004Difficulty 64 (Academic)
Research methods in ecology
Clements, Frederic E. (Frederic Edward)
1,049 Gutenberg downloadsen2024Difficulty 50 (College)
General Anatomy, Applied to Physiology and Medicine, Vol. 1 (of 3)
Bichat, Xavier
1,048 Gutenberg downloadsen2017Difficulty 67 (Academic)
American Weasels
Hall, E. Raymond (Eugene Raymond)
1,045 Gutenberg downloadsen2013Difficulty 63 (Academic)
The alligator and its allies
Reese, A. M. (Albert Moore)
1,045 Gutenberg downloadsen2023Difficulty 53 (Graduate)
Nests and Eggs of Birds of the United States Illustrated
Gentry, Thomas G. (Thomas George)
1,039 Gutenberg downloadsen2014Difficulty 60 (Graduate)
Animals of the Past
Lucas, Frederic A. (Frederic Augustus)
1,038 Gutenberg downloadsen2011Difficulty 60 (Graduate)
Syndrome
Hoover, Thomas
1,037 Gutenberg downloadsen2010Difficulty 42 (College)
A History of Science — Volume 4
Williams, Henry Smith & Williams, Edward Huntington
1,036 Gutenberg downloadsen1999Difficulty 68 (Academic)
Lives of Eminent Zoologists, from Aristotle to Linnæus with Introductory remarks on the Study of Natural History
MacGillivray, William
1,036 Gutenberg downloadsen2010Difficulty 84 (Specialist)
Histoire des légumes
Gibault, Georges
1,035 Gutenberg downloadsfr2021
Rust, Smut, Mildew, & Mould: An Introduction to the Study of Microscopic Fungi
Cooke, M. C. (Mordecai Cubitt)
1,035 Gutenberg downloadsen2020Difficulty 61 (Academic)
The Bacillus of Long Life A Manual of the Preparation and Souring of Milk for Dietary Purposes, Together with an Historical Account of the Use of Fermented Milks, from the Earliest Times to the Present Day, and Their Wonderful Effect in the Prolonging of Human Existence
Douglas, Loudon M.
1,034 Gutenberg downloadsen2010Difficulty 56 (Graduate)
The Homing Pigeon
United States. Army. Signal Corps & United States. War Department
1,032 Gutenberg downloadsen2017Difficulty 51 (Graduate)
Aspects of nature, in different lands and different climates (Vol. 2 of 2) with scientific elucidations
Humboldt, Alexander von
1,029 Gutenberg downloadsen2022Difficulty 72 (Expert)
Travels on the Amazon
Wallace, Alfred Russel
1,029 Gutenberg downloadsen2016Difficulty 65 (Academic)
An anatomical disquisition on the motion of the heart & blood in animals
Harvey, William
1,027 Gutenberg downloadsen2022Difficulty 62 (Academic)
Man's Place in Nature, and Other Essays
Huxley, Thomas Henry
1,024 Gutenberg downloadsen2012Difficulty 65 (Academic)
Our Domestic Birds: Elementary Lessons in Aviculture
Robinson, John H. (John Henry)
1,022 Gutenberg downloadsen2010Difficulty 61 (Academic)
Index of the Project Gutenberg Works of Charles Darwin
Darwin, Charles
1,017 Gutenberg downloadsen2019Difficulty 88 (Specialist)
A Text-Book of Horseshoeing, for Horseshoers and Veterinarians
Lungwitz, A. (Anton)
1,013 Gutenberg downloadsen2021Difficulty 55 (Graduate)
Our Summer Migrants An Account of the Migratory Birds Which Pass the Summer in the British Islands.
Harting, James Edmund
1,011 Gutenberg downloadsen2019Difficulty 57 (Graduate)
The book of antelopes, vol. 4 (of 4)
Sclater, Philip Lutley & Thomas, Oldfield
1,010 Gutenberg downloadsen2023Difficulty 48 (College)
Wild Animals of North America Intimate Studies of Big and Little Creatures of the Mammal Kingdom
Nelson, Edward William
1,010 Gutenberg downloadsen2019Difficulty 52 (Graduate)
The Science and Philosophy of the Organism
Driesch, Hans
1,009 Gutenberg downloadsen2013Difficulty 67 (Academic)
Animal intelligence: Experimental studies
Thorndike, Edward L. (Edward Lee)
1,006 Gutenberg downloadsen2023Difficulty 65 (Academic)
Botanical features of the Algerian Sahara
Cannon, William Austin
1,003 Gutenberg downloadsen2023Difficulty 52 (Graduate)
Lehrbuch der Botanik für Hochschulen
Strasburger, Eduard & Noll, Fritz & Schenck, H. (Heinrich) & Schimper, A. F. W. (Andreas Franz Wilhelm)
1,001 Gutenberg downloadsde2020
Buffon's Natural History. Volume 09 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
Buffon, Georges Louis Leclerc, comte de
1,000 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Comparative Breeding Behavior of Ammospiza caudacuta and A. maritima
Woolfenden, Glen Everett
1,000 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Keys to Fungi on Dung
Richardson, M. J. (Michael J.) & Watling, Roy
994 Gutenberg downloadsen2018Difficulty 57 (Graduate)
The Birds of Australia, Vol. 1 of 7
Gould, John
993 Gutenberg downloadsen2021Difficulty 45 (College)
The Snakes of Europe
Boulenger, George Albert
993 Gutenberg downloadsen2014Difficulty 63 (Academic)
Life histories of North American wood warblers, Part 1 (of 2)
Bent, Arthur Cleveland
981 Gutenberg downloadsen2012Difficulty 66 (Academic)
The Anatomy of the Human Peritoneum and Abdominal Cavity Considered from the Standpoint of Development and Comparative Anatomy
Huntington, George S. (George Sumner)
978 Gutenberg downloadsen2013Difficulty 67 (Academic)
Journals of Travels in Assam, Burma, Bhootan, Afghanistan and the Neighbouring Countries
Griffith, William
977 Gutenberg downloadsen2005Difficulty 54 (Graduate)
The Courtship of Animals
Pycraft, W. P. (William Plane)
975 Gutenberg downloadsen2019Difficulty 66 (Academic)
Journal of the Proceedings of the Linnean Society - Vol. 3 Zoology
Linnean Society of London
972 Gutenberg downloadsen2007Difficulty 62 (Academic)
The botanist's repository for new and rare plants; vol. 01 & 02 [of 10]
Andrews, Henry Cranke, active 1799-1828
972 Gutenberg downloadsen2023Difficulty 57 (Graduate)
Darwinism and Race Progress
Haycraft, John Berry
971 Gutenberg downloadsen2014Difficulty 71 (Expert)
Life of Charles Darwin
Bettany, G. T. (George Thomas)
971 Gutenberg downloadsen2009Difficulty 63 (Academic)
Mutual Aid: A Factor of Evolution
Kropotkin, Petr Alekseevich, kniaz
970 Gutenberg downloadsen2003Difficulty 73 (Expert)
The Academic Gregories
Stewart, Agnes Grainger
968 Gutenberg downloadsen2016Difficulty 59 (Graduate)
The Dinosaur Quarry. Dinosaur National Monument, Colorado-Utah
Good, John M. (John Maxwell) & Stucker, Gilbert F. & White, Theodore Elmer
968 Gutenberg downloadsen2015Difficulty 54 (Graduate)
Field and Woodland Plants
Furneaux, William S.
967 Gutenberg downloadsen2013Difficulty 52 (Graduate)
Common Science
Washburne, Carleton
964 Gutenberg downloadsen2009Difficulty 48 (College)
Inquiries into human faculty and its development
Galton, Francis
964 Gutenberg downloadsen2004Difficulty 79 (Expert)
Elements of Structural and Systematic Botany For High Schools and Elementary College Courses
Campbell, Douglas Houghton
963 Gutenberg downloadsen2007Difficulty 57 (Graduate)
The apiary; or, bees, bee-hives, and bee culture [1865] Being a familiar account of the habits of bees, and the most improved methods of management, with full directions, adapted for the cottager, farmer, or scientific apiarian
Neighbor, Alfred
962 Gutenberg downloadsen2022Difficulty 63 (Academic)
Notes and Letters on the Natural History of Norfolk More Especially on the Birds and Fishes
Browne, Thomas, Sir
961 Gutenberg downloadsen2011Difficulty 62 (Academic)
The micro-organisms of the soil
Russell, Edward J. (Edward John) & Rothamsted Experimental Station
961 Gutenberg downloadsen2022Difficulty 62 (Academic)
The Natural History of Cage Birds Their Management, Habits, Food, Diseases, Treatment, Breeding, and the Methods of Catching Them.
Bechstein, Johann Matthäus
961 Gutenberg downloadsen2012Difficulty 56 (Graduate)
The case against evolution
O'Toole, George Barry
959 Gutenberg downloadsen2022Difficulty 69 (Academic)
The Sea Shore
Furneaux, William S.
959 Gutenberg downloadsen2013Difficulty 49 (College)
Migration of Birds (1950)
Lincoln, Frederick Charles
955 Gutenberg downloadsen2021Difficulty 70 (Academic)
The Moths of the British Isles, Second Series Comprising the Families Noctuidæ to Hepialidæ
South, Richard
952 Gutenberg downloadsen2013Difficulty 50 (College)
Appletons' Popular Science Monthly, April 1899 Volume LIV, No. 6, April 1899
Various
950 Gutenberg downloadsen2013Difficulty 56 (Graduate)
Scientific American, Vol. XXXIX.No. 6. [New Series.], August 10, 1878
Various
949 Gutenberg downloadsen2013Difficulty 54 (Graduate)
Greek Biology & Greek Medicine
Singer, Charles
948 Gutenberg downloadsen2020Difficulty 56 (Graduate)
Louis Pasteur: His Life and Labours
Vallery-Radot, René
944 Gutenberg downloadsen2014Difficulty 59 (Graduate)
Sanitation in Panama
Gorgas, William Crawford
942 Gutenberg downloadsen2023Difficulty 56 (Graduate)
The Study of Plant Life
Stopes, Marie Carmichael
942 Gutenberg downloadsen2019Difficulty 43 (College)
Response in the Living and Non-Living
Bose, Jagadis Chandra
941 Gutenberg downloadsen2006Difficulty 65 (Academic)
The anatomy of the domestic fowl
Kaupp, B. F. (Benjamin Franklyn)
939 Gutenberg downloadsen2023Difficulty 65 (Academic)
The Wonders of Instinct: Chapters in the Psychology of Insects
Fabre, Jean-Henri
939 Gutenberg downloadsen2003Difficulty 50 (College)
The History of Creation, Vol. 1 (of 2) Or the Development of the Earth and its Inhabitants by the Action of Natural Causes
Haeckel, Ernst
936 Gutenberg downloadsen2012Difficulty 64 (Academic)
Butterflies Worth Knowing
Weed, Clarence Moores
935 Gutenberg downloadsen2011Difficulty 66 (Academic)
The Life of Crustacea
Calman, W. T. (William Thomas)
935 Gutenberg downloadsen2012Difficulty 51 (Graduate)
Charles Darwin and the Theory of Natural Selection
Poulton, Edward Bagnall, Sir
931 Gutenberg downloadsen2021Difficulty 60 (Graduate)
Monism as Connecting Religion and Science A Man of Science
Haeckel, Ernst
931 Gutenberg downloadsen2005Difficulty 74 (Expert)
The Riddle of the Universe at the close of the nineteenth century
Haeckel, Ernst
930 Gutenberg downloadsen2013Difficulty 72 (Expert)
A History of Science — Volume 1
Williams, Henry Smith & Williams, Edward Huntington
926 Gutenberg downloadsen1999Difficulty 65 (Academic)
British Museum (Natural History) General Guide
British Museum (Natural History)
926 Gutenberg downloadsen2018Difficulty 69 (Academic)
American Forest Trees
Gibson, Henry H.
923 Gutenberg downloadsen2013Difficulty 50 (College)
Illustrations of Exotic Entomology, Volume 2
Drury, Dru
923 Gutenberg downloadsen2014Difficulty 55 (Graduate)
The Fishing Industry
Gibbs, William E. (William Edward)
919 Gutenberg downloadsen2016Difficulty 54 (Graduate)
The Origin of Vertebrates
Gaskell, Walter Holbrook
917 Gutenberg downloadsen2013Difficulty 82 (Specialist)
Student's Hand-book of Mushrooms of America, Edible and Poisonous
Taylor, Thomas
915 Gutenberg downloadsen2010Difficulty 60 (Graduate)
The physiology of digestion considered with relation to the principles of dietetics
Combe, Andrew
913 Gutenberg downloadsen2023Difficulty 83 (Specialist)
The Lives of Celebrated Travellers, Vol. 2 (of 3)
St. John, James Augustus
912 Gutenberg downloadsen2021Difficulty 90 (Specialist)
The Whence and the Whither of Man A Brief History of His Origin and Development through Conformity to Environment; Being the Morse Lectures of 1895
Tyler, John M. (John Mason)
911 Gutenberg downloadsen2005Difficulty 53 (Graduate)
The Chautauquan, Vol. 04, October 1883
Chautauqua Literary and Scientific Circle & Chautauqua Institution
910 Gutenberg downloadsen2016Difficulty 50 (College)
More Hunting Wasps
Fabre, Jean-Henri
907 Gutenberg downloadsen2002Difficulty 48 (College)
Links With the Past in the Plant World
Seward, A. C. (Albert Charles)
906 Gutenberg downloadsen2020Difficulty 65 (Academic)
The Fantastic Clan: The Cactus Family
Thornber, J. J. (John James) & Bonker, Frances
906 Gutenberg downloadsen2014Difficulty 67 (Academic)
Harvesting Ants and Trap-Door Spiders Notes and Observations on Their Habits and Dwellings
Moggridge, John Traherne
903 Gutenberg downloadsen2021Difficulty 54 (Graduate)
Lectures and Essays
Huxley, Thomas Henry
902 Gutenberg downloadsen2005Difficulty 58 (Graduate)
The North American Slime-Moulds A Descriptive List of All Species of Myxomycetes Hitherto Reported from the Continent of North America, with Notes on Some Extra-Limital Species
Macbride, Thomas H. (Thomas Huston)
900 Gutenberg downloadsen2010Difficulty 63 (Academic)
Phrenology Examined
Flourens, P. (Pierre)
898 Gutenberg downloadsen2021Difficulty 59 (Graduate)
The book of antelopes, vol. 2 (of 4)
Sclater, Philip Lutley & Thomas, Oldfield
892 Gutenberg downloadsen2023Difficulty 48 (College)
Scientific American Supplement, No. 841, February 13, 1892
Various
889 Gutenberg downloadsen2005Difficulty 52 (Graduate)
Animal Intelligence The International Scientific Series, Vol. XLIV.
Romanes, George John
887 Gutenberg downloadsen2012Difficulty 58 (Graduate)
The human species
Quatrefages, A. de (Armand de)
887 Gutenberg downloadsen2023Difficulty 56 (Graduate)
Louis Agassiz: His Life and Correspondence
Agassiz, Louis
886 Gutenberg downloadsen2004Difficulty 49 (College)
Significant Achievements in Space Bioscience 1958-1964
United States. National Aeronautics and Space Administration
886 Gutenberg downloadsen2012Difficulty 76 (Expert)
Neotropical Hylid Frogs, Genus Smilisca
Duellman, William Edward & Trueb, Linda
884 Gutenberg downloadsen2011Difficulty 60 (Graduate)
The Farmer's Veterinarian: A Practical Treatise on the Diseases of Farm Stock
Burkett, Charles William
882 Gutenberg downloadsen2017Difficulty 49 (College)
Desert and water gardens of the Red Sea : $b Being an account of the natives and the shore formations of the coast
Crossland, Cyril
880 Gutenberg downloadsen2023Difficulty 50 (College)
Appletons' Popular Science Monthly, July 1899 Volume LV, No. 3, July 1899
Various
876 Gutenberg downloadsen2014Difficulty 58 (Graduate)
Science & Education: Essays
Huxley, Thomas Henry
876 Gutenberg downloadsen2004Difficulty 72 (Expert)
The Movements and Habits of Climbing Plants
Darwin, Charles
874 Gutenberg downloadsen2001Difficulty 60 (Graduate)
Darwinism stated by Darwin himself Characteristic passages from the writings of Charles Darwin
Darwin, Charles
871 Gutenberg downloadsen2022Difficulty 64 (Academic)
A Mechanical Account of Poisons in Several Essays
Mead, Richard
870 Gutenberg downloadsen2016Difficulty 73 (Expert)
Barium: A Cause of the Loco-Weed Disease
Crawford, Albert C. (Albert Cornelius)
870 Gutenberg downloadsen2012Difficulty 57 (Graduate)
Abstracts of Papers Read at the First International Eugenics Congress University of London, July, 1912
International Eugenics Congress (1st : 1912 : London)
869 Gutenberg downloadsen2014Difficulty 65 (Academic)
Glaucus; Or, The Wonders of the Shore
Kingsley, Charles
868 Gutenberg downloadsen1996Difficulty 57 (Graduate)
Haeckel : $b his life and work
Bölsche, Wilhelm
868 Gutenberg downloadsen2023Difficulty 53 (Graduate)
The Monist, Vol. 1, 1890-1891 : $b A quarterly magazine
Various
865 Gutenberg downloadsen2018Difficulty 64 (Academic)
Cassell's book of birds; vol. 2
Brehm, Alfred Edmund
864 Gutenberg downloadsen2018Difficulty 58 (Graduate)
Supplement to Harvesting Ants and Trap-Door Spiders
Moggridge, John Traherne & Pickard-Cambridge, Octavius
863 Gutenberg downloadsen2021Difficulty 59 (Graduate)
The Mason-Bees
Fabre, Jean-Henri
862 Gutenberg downloadsen2001Difficulty 51 (Graduate)
Apes and Monkeys: Their Life and Language
Garner, R. L. (Richard Lynch)
860 Gutenberg downloadsen2022Difficulty 55 (Graduate)
Appletons' Popular Science Monthly, March 1899 Volume LIV, No. 5, March 1899
Various
860 Gutenberg downloadsen2013Difficulty 57 (Graduate)
Artistic Anatomy of Animals
Cuyer, Édouard
860 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Flowers of the Southwest Deserts
Dodge, Natt N. (Natt Noyes)
860 Gutenberg downloadsen2016Difficulty 61 (Academic)
The Human Side of Animals
Dixon, Royal
860 Gutenberg downloadsen2006Difficulty 58 (Graduate)
Graphic illustrations of abortion and the diseases of menstruation Consisting of Twelve Plates from Drawings Engraved on Stone, and Coloured by Mr. J. Perry, and Two Copper-plates from the Philosophical Transactions, Coloured by the Same Artist. the Whole Representing Forty-five Specimens of Aborted Ova and Adventitious Productions of the Uterus, With Preliminary Observations, Explanations of the Figures and Remarks, Anatomical and Physiological.
Granville, A. B. (Augustus Bozzi)
858 Gutenberg downloadsen2019Difficulty 61 (Academic)
The fauna of the deep sea
Hickson, Sydney J. (Sydney John)
858 Gutenberg downloadsen2021Difficulty 63 (Academic)
The Wonders of Life: A Popular Study of Biological Philosophy
Haeckel, Ernst
858 Gutenberg downloadsen2014Difficulty 68 (Academic)
Lameness of the Horse Veterinary Practitioners' Series, No. 1
Lacroix, John Victor
857 Gutenberg downloadsen2005Difficulty 65 (Academic)
American Pomology. Apples
Warder, J. A. (John Aston)
851 Gutenberg downloadsen2011Difficulty 64 (Academic)
William Harvey and the Discovery of the Circulation of the Blood
Huxley, Thomas Henry
849 Gutenberg downloadsen2001Difficulty 62 (Academic)
The botanist's repository for new and rare plants; vol. 03 & 04 [of 10]
Andrews, Henry Cranke, active 1799-1828
846 Gutenberg downloadsen2024Difficulty 55 (Graduate)
The Story of Milk
Frederiksen, Johan Ditlev
846 Gutenberg downloadsen2021Difficulty 64 (Academic)
A Handbook of Some South Indian Grasses
Rangachari, K. & Tadulinga Mudaliyar, C.
844 Gutenberg downloadsen2007Difficulty 50 (College)
An Inquiry into the Causes and Effects of the Variolae Vaccinae A Disease Discovered in Some of the Western Counties of England, Particularly Gloucestershire, and Known by the Name of the Cow Pox
Jenner, Edward
843 Gutenberg downloadsen2009Difficulty 60 (Graduate)
Journal of Entomology and Zoology, Vol. 09, No. 1, March 1917
Various
843 Gutenberg downloadsen2015Difficulty 53 (Graduate)
Lectures and Essays
Huxley, Thomas Henry
843 Gutenberg downloadsen2004Difficulty 63 (Academic)
Useful Knowledge: Volume 3. Animals Or, a familiar account of the various productions of nature
Bingley, William
841 Gutenberg downloadsen2018Difficulty 54 (Graduate)
Aspects of plant life; with special reference to the British flora
Praeger, R. Lloyd (Robert Lloyd)
837 Gutenberg downloadsen2018Difficulty 59 (Graduate)
Territory in Bird Life
Howard, Henry Eliot
837 Gutenberg downloadsen2010Difficulty 62 (Academic)
Aromatics and the Soul: A Study of Smells
McKenzie, Dan
835 Gutenberg downloadsen2019Difficulty 53 (Graduate)
General Anatomy, Applied to Physiology and Medicine, Vol. 2 (of 3)
Bichat, Xavier
828 Gutenberg downloadsen2017Difficulty 61 (Academic)
A guide to the shell and starfish galleries : $b (Mollusca, Polyzoa, Brachiopoda, Tunicata, Echinoderma, and Worms)
British Museum (Natural History). Department of Zoology & Bell, F. J. (Francis Jeffrey) & Kirkpatrick, R. (Randolph) & Smith, E. A. (Edgar Albert)
827 Gutenberg downloadsen2024Difficulty 59 (Graduate)
Buffon's Natural History, Volume 01 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Mineral, &c. &c
Buffon, Georges Louis Leclerc, comte de
826 Gutenberg downloadsen2014Difficulty 76 (Expert)
Common objects of the microscope
Wood, J. G. (John George)
826 Gutenberg downloadsen2017Difficulty 69 (Academic)
A narrative of travels on the Amazon and Rio Negro, : $b with an account of the native tribes, and observations on the climate, geology, and natural history of the Amazon valley
Wallace, Alfred Russel
825 Gutenberg downloadsen2023Difficulty 65 (Academic)
A Historical Account of Useful Inventions and Scientific Discoveries Being a manual of instruction and entertainment.
Grant, George
823 Gutenberg downloadsen2016Difficulty 62 (Academic)
Bramble-Bees and Others
Fabre, Jean-Henri
820 Gutenberg downloadsen2002Difficulty 52 (Graduate)
Essays on Darwinism
Stebbing, Thomas Roscoe Rede
820 Gutenberg downloadsen2015Difficulty 63 (Academic)
The Naturalist's Repository, Volume 1 (of 5) or Monthly Miscellany of Exotic Natural History: etc. etc.
Donovan, E. (Edward)
819 Gutenberg downloadsen2017Difficulty 76 (Expert)
The History of the European Fauna
Scharff, R. F. (Robert Francis)
818 Gutenberg downloadsen2010Difficulty 61 (Academic)
Finger prints
Galton, Francis
817 Gutenberg downloadsen2011Difficulty 62 (Academic)
The Natural Philosophy of Love
Gourmont, Remy de
815 Gutenberg downloadsen2014Difficulty 56 (Graduate)
Wayside and woodland trees : $b a pocket guide to the British sylva
Step, Edward
815 Gutenberg downloadsen2010Difficulty 53 (Graduate)
The book of antelopes, vol. 3 (of 4)
Sclater, Philip Lutley & Thomas, Oldfield
814 Gutenberg downloadsen2023Difficulty 45 (College)
The Fundamentals of Bacteriology
Morrey, Charles Bradfield
812 Gutenberg downloadsen2013Difficulty 67 (Academic)
Water Reptiles of the Past and Present
Williston, Samuel Wendell
811 Gutenberg downloadsen2022Difficulty 63 (Academic)
Dragons of the Air: An Account of Extinct Flying Reptiles
Seeley, H. G. (Harry Govier)
809 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Nature readers : $b Sea-side and way-side. No. 4
Wright, Julia McNair
809 Gutenberg downloadsen2023Difficulty 45 (College)
Illustrations of the Birds of California, Texas, Oregon, British and Russian America
Cassin, John
808 Gutenberg downloadsen2021Difficulty 63 (Academic)
A Report upon the Mollusk Fisheries of Massachusetts
Massachusetts. Commissioners on Fisheries and Game & Belding, David Lawrence
807 Gutenberg downloadsen2015Difficulty 67 (Academic)
The Geographical Distribution of Animals, Volume 1 With a study of the relations of living and extinct faunas as elucidating the past changes of the Earth's surface
Wallace, Alfred Russel
807 Gutenberg downloadsen2018Difficulty 58 (Graduate)
Scientific American, Volume XXXVI., No. 8, February 24, 1877 A Weekly Journal of Practical Information, Art, Science, Mechanics, Chemistry, and Manufactures.
Various
806 Gutenberg downloadsen2006Difficulty 54 (Graduate)
Falling in Love; With Other Essays on More Exact Branches of Science
Allen, Grant
804 Gutenberg downloadsen2005Difficulty 64 (Academic)
Through a pocket lens
Scherren, Henry
804 Gutenberg downloadsen2022Difficulty 43 (College)
The Common Spiders of the United States
Emerton, J. H. (James Henry)
801 Gutenberg downloadsen2013Difficulty 45 (College)
Half hours with the lower animals : $b protozoans, sponges, corals, shells, insects, and crustaceans
Holder, Charles Frederick
799 Gutenberg downloadsen2016Difficulty 51 (Graduate)
A History of Science — Volume 5
Williams, Henry Smith & Williams, Edward Huntington
798 Gutenberg downloadsen2009Difficulty 57 (Graduate)
History of biology
Miall, L. C. (Louis Compton)
796 Gutenberg downloadsen2018Difficulty 61 (Academic)
Directions for Collecting and Preserving Insects
Riley, Charles V. (Charles Valentine)
795 Gutenberg downloadsen2012Difficulty 70 (Academic)
Life and Letters of Thomas Henry Huxley — Volume 1
Huxley, Thomas Henry
794 Gutenberg downloadsen2004Difficulty 58 (Graduate)
Trees of the Northern United States Their Study, Description and Determination
Apgar, A. C. (Austin Craig)
793 Gutenberg downloadsen2009Difficulty 53 (Graduate)
Grasses : $b A handbook for use in the field and laboratory
Ward, H. Marshall (Harry Marshall)
792 Gutenberg downloadsen2015Difficulty 56 (Graduate)
The Avifauna of Micronesia, Its Origin, Evolution, and Distribution
Baker, Rollin H. (Rollin Harold)
792 Gutenberg downloadsen2013Difficulty 61 (Academic)
Personality of plants
Dixon, Royal & Fitch, Franklyn Everett
790 Gutenberg downloadsen2022Difficulty 54 (Graduate)
Illustrations of Exotic Entomology, Volume 3
Drury, Dru
789 Gutenberg downloadsen2014Difficulty 57 (Graduate)
Book of monsters : $b Portraits and biographies of a few of the inhabitants of woodland and meadow
Fairchild, David & Fairchild, Marian
787 Gutenberg downloadsen2012Difficulty 55 (Graduate)
Being Well-Born: An Introduction to Eugenics
Guyer, Michael F. (Michael Frederic)
784 Gutenberg downloadsen2012Difficulty 85 (Specialist)
Disease in plants
Ward, H. Marshall (Harry Marshall)
784 Gutenberg downloadsen2012Difficulty 66 (Academic)
Wasps, Social and Solitary
Peckham, George W. (George Williams) & Peckham, E. G. (Elizabeth Gifford)
784 Gutenberg downloadsen2014Difficulty 60 (Graduate)
Extinct birds : $b An attempt to unite in one volume a short account of those birds which have become extinct in historical times
Rothschild, Lionel Walter Rothschild, Baron
781 Gutenberg downloadsen2012Difficulty 55 (Graduate)
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, Plates Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76, Vol. XVIII
Haeckel, Ernst
781 Gutenberg downloadsen2013Difficulty 53 (Graduate)
A Synopsis of the British Mosses Containing Descriptions of All the Genera and Species, (With Localities of the Rarer Ones) Found in Great Britain and Ireland, Based Upon Wilson's "Bryologia Britannica," Schimper's "Synopsis," Etc.
Hobkirk, Charles C. P. (Charles Codrington Pressick)
779 Gutenberg downloadsen2021Difficulty 63 (Academic)
Insects and Diseases of Trees in the South
Anonymous
778 Gutenberg downloadsen2015Difficulty 55 (Graduate)
Metabolic Adaptation to Climate and Distribution of the Raccoon Procyon Lotor and Other Procyonidae
Mugaas, John N. & Mahlke-Johnson, Kathleen P. & Seidensticker, John
778 Gutenberg downloadsen2011Difficulty 74 (Expert)
Buchanan's Journal of Man, August 1887 Volume 1, Number 7
Unknown
775 Gutenberg downloadsen2008Difficulty 63 (Academic)
Lachesis Lapponica; Or, A Tour in Lapland, Volume 1
Linné, Carl von
775 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Mammals of the Southwest Mountains and Mesas
Olin, George
775 Gutenberg downloadsen2016Difficulty 57 (Graduate)
Marine Protozoa from Woods Hole Bulletin of the United States Fish Commission 21:415-468, 1901
Calkins, Gary N. (Gary Nathan)
775 Gutenberg downloadsen2006Difficulty 56 (Graduate)
A Review of the Systems of Ethics Founded on the Theory of Evolution
Williams, Cora May
772 Gutenberg downloadsen2012Difficulty 100 (Quantum Electrodynamics)
The Last Link: Our Present Knowledge of the Descent of Man
Haeckel, Ernst
772 Gutenberg downloadsen2013Difficulty 63 (Academic)
The Popular Science Monthly, June, 1900 Vol. 57, May, 1900 to October, 1900
Various
772 Gutenberg downloadsen2014Difficulty 69 (Academic)
Domesticated animals : $b Their relation to man and to his advancement in civilization
Shaler, Nathaniel Southgate
771 Gutenberg downloadsen2008Difficulty 63 (Academic)
The Chautauquan, Vol. 05, June 1885, No. 9
Chautauqua Literary and Scientific Circle & Chautauqua Institution
771 Gutenberg downloadsen2017Difficulty 53 (Graduate)
The Recent Mammals of Tamaulipas, México
Alvarez, Ticul
771 Gutenberg downloadsen2012Difficulty 56 (Graduate)
The Tower Menagerie : $b comprising the natural history of the animals contained in that establishment; with anecdotes of their characters and history.
Bennett, Edward Turner
770 Gutenberg downloadsen2016Difficulty 77 (Expert)
A Synopsis of the North American Lagomorpha
Hall, E. Raymond (Eugene Raymond)
769 Gutenberg downloadsen2010Difficulty 53 (Graduate)
The Elements of Botany, For Beginners and For Schools
Gray, Asa
769 Gutenberg downloadsen2010Difficulty 57 (Graduate)
What is Darwinism?
Hodge, Charles
768 Gutenberg downloadsen2006Difficulty 53 (Graduate)
The Amphibians and Reptiles of Michoacán, México
Duellman, William Edward
765 Gutenberg downloadsen2010Difficulty 63 (Academic)
Beautiful shells : $b Their nature, structure, and uses familiarly explained; with directions for collecting, cleaning, and arranging them in the cabinet; descriptions of the most remarkable species, and of the creatures which inhabit them; and explanations of the meanings of their scientific names, and of the terms used in conchology
Adams, H. G. (Henry Gardiner)
764 Gutenberg downloadsen2024Difficulty 66 (Academic)
Natural History of Cottonmouth Moccasin, Agkistrodon piscovorus (Reptilia)
Burkett, Ray D.
764 Gutenberg downloadsen2011Difficulty 63 (Academic)
Experiments on Animals
Paget, Stephen
763 Gutenberg downloadsen2013Difficulty 59 (Graduate)
Studies in the Evolutionary Psychology of Feeling
Stanley, Hiram Miner
760 Gutenberg downloadsen2018Difficulty 62 (Academic)
A Manual of Conchology According to the System Laid Down by Lamarck, with the Late Improvements by De Blainville. Exemplified and Arranged for the Use of Students.
Wyatt, Thomas
759 Gutenberg downloadsen2018Difficulty 58 (Graduate)
Drawings and Pharmacy in Al-Zahrawi's 10th-Century Surgical Treatise
Hamarneh, Sami Khalaf
759 Gutenberg downloadsen2008Difficulty 62 (Academic)
The Botanical Magazine, Vol. 01 Or, Flower-Garden Displayed
Curtis, William
759 Gutenberg downloadsen2005Difficulty 57 (Graduate)
The Universal Kinship
Moore, J. Howard (John Howard)
759 Gutenberg downloadsen2020Difficulty 54 (Graduate)
Sea-Weeds, Shells and Fossils
Gray, Peter & Woodward, B. B. (Bernard Bolingbroke)
757 Gutenberg downloadsen2011Difficulty 58 (Graduate)
Journal of the Proceedings of the Linnean Society - Vol. 4 Zoology
Linnean Society of London
756 Gutenberg downloadsen2014Difficulty 61 (Academic)
An Elementary Text-book of the Microscope including a description of the methods of preparing and mounting objects, etc.
Griffith, J. W. (John William)
755 Gutenberg downloadsen2015Difficulty 52 (Graduate)
Self-Organizing Systems, 1963
Unknown
755 Gutenberg downloadsen2021Difficulty 72 (Expert)
The Breath of Life
Burroughs, John
754 Gutenberg downloadsen2006Difficulty 57 (Graduate)
Handbook of the Trees of New England
Dame, Lorin Low & Brooks, Henry M. (Henry Mason)
752 Gutenberg downloadsen2007Difficulty 53 (Graduate)
The Genetic Effects of Radiation
Asimov, Isaac & Dobzhansky, Theodosius
752 Gutenberg downloadsen2017Difficulty 59 (Graduate)
Woman and Womanhood: A Search for Principles
Saleeby, C. W. (Caleb Williams)
752 Gutenberg downloadsen2006Difficulty 59 (Graduate)
A Monograph on the Sub-class Cirripedia (Volume 2 of 2) The Balanidæ, (or Sessile Cirripedes); the Verrucidæ, etc., etc.
Darwin, Charles
750 Gutenberg downloadsen2014Difficulty 57 (Graduate)
The Different Forms of Flowers on Plants of the Same Species
Darwin, Charles
749 Gutenberg downloadsen2003Difficulty 62 (Academic)
The Story of Evolution
McCabe, Joseph
749 Gutenberg downloadsen1997Difficulty 56 (Graduate)
Appletons' Popular Science Monthly, May, 1900 Vol. 57, May, 1900 to October, 1900
Various
745 Gutenberg downloadsen2014Difficulty 60 (Graduate)
Mental Radio
Sinclair, Upton
744 Gutenberg downloadsen2020Difficulty 52 (Graduate)
Physiology: The Science of the Body
Martin, Ernest G.
743 Gutenberg downloadsen2015Difficulty 53 (Graduate)
Pioneers of Evolution from Thales to Huxley With an Intermediate Chapter on the Causes of Arrest of the Movement
Clodd, Edward
743 Gutenberg downloadsen2012Difficulty 58 (Graduate)
Species and Varieties, Their Origin by Mutation
Vries, Hugo de
742 Gutenberg downloadsen2005Difficulty 60 (Graduate)
Prehistoric man
Duckworth, W. L. H. (Wynfrid Laurence Henry)
740 Gutenberg downloadsen2013Difficulty 57 (Graduate)
The Lobster Fishery of Maine Bulletin of the United States Fish Commission, Vol. 19, Pages 241-265, 1899
Cobb, John N. (John Nathan)
740 Gutenberg downloadsen2006Difficulty 51 (Graduate)
Foreign Butterflies
Duncan, James
739 Gutenberg downloadsen2018Difficulty 56 (Graduate)
An Account of the Insects Noxious to Agriculture and Plants in New Zealand The Scale Insects (Coccididae)
Maskell, William Miles
738 Gutenberg downloadsen2015Difficulty 53 (Graduate)
Living lights : $b A popular account of phosphorescent animals and vegetables
Holder, Charles Frederick
738 Gutenberg downloadsen2025Difficulty 58 (Graduate)
The Orchid Album, Volume 3 Comprising Coloured Figures and Descriptions of New, Rare, and Beautiful Orchidaceous Plants
Moore, Thomas
738 Gutenberg downloadsen2019Difficulty 57 (Graduate)
Guide to the study of animal ecology
Adams, Charles C. (Charles Christopher)
737 Gutenberg downloadsen2023Difficulty 66 (Academic)
Animal Behaviour
Morgan, C. Lloyd (Conwy Lloyd)
735 Gutenberg downloadsen2017Difficulty 56 (Graduate)
An Account of the Late Improvements in Galvanism With a Series of Curious and Interesting Experiments Performed Before the Commissioners of the French National Institute, and Repeated Lately in the Anatomical Theatres of London
Aldini, Giovanni
734 Gutenberg downloadsen2018Difficulty 64 (Academic)
Scientific American Supplement, No. 799, April 25, 1891
Various
734 Gutenberg downloadsen2004Difficulty 50 (College)
Whale hunting with gun and camera A naturalist's account of the modern shore-whaling industry, of whales and their habits, and of hunting experiences in various parts of the world
Andrews, Roy Chapman
733 Gutenberg downloadsen2022Difficulty 87 (Specialist)
The flowering plants of South Africa; vol. 3
Pole Evans, I. B. (Illtyd Buller)
732 Gutenberg downloadsen2021Difficulty 52 (Graduate)
The Barren Ground Caribou of Keewatin
Harper, Francis
730 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Some Reptiles and Amphibians from Korea
Webb, Robert G. (Robert Gravem) & Byers, George William & Jones, J. Knox
729 Gutenberg downloadsen2011Difficulty 57 (Graduate)
Scientific American Supplement, No. 598, June 18, 1887
Various
727 Gutenberg downloadsen2004Difficulty 50 (College)
The Popular Science Monthly, October, 1900 Vol. 57, May, 1900 to October, 1900
Various
727 Gutenberg downloadsen2014Difficulty 75 (Expert)
Zoological Illustrations, Volume 1 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
727 Gutenberg downloadsen2012Difficulty 64 (Academic)
Buffon's Natural History. Volume 05 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
Buffon, Georges Louis Leclerc, comte de
726 Gutenberg downloadsen2014Difficulty 65 (Academic)
An elementary manual of New Zealand entomology : $b being an introduction to the study of our native insects
Hudson, G. V. (George Vernon)
725 Gutenberg downloadsen2013Difficulty 54 (Graduate)
The Life-Story of Insects
Carpenter, George H. (George Herbert)
724 Gutenberg downloadsen2005Difficulty 57 (Graduate)
The Effects of Cross & Self-Fertilisation in the Vegetable Kingdom
Darwin, Charles
721 Gutenberg downloadsen2003Difficulty 61 (Academic)
Buffon's Natural History. Volume 04 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
Buffon, Georges Louis Leclerc, comte de
720 Gutenberg downloadsen2014Difficulty 56 (Graduate)
Colouration in Animals and Plants
Tylor, Alfred
720 Gutenberg downloadsen2014Difficulty 56 (Graduate)
Bee-keeping for profit
Morley, W. S.
719 Gutenberg downloadsen2022Difficulty 53 (Graduate)
The Chemistry of Plant Life
Thatcher, Roscoe Wilfred
719 Gutenberg downloadsen2010Difficulty 88 (Specialist)
British Bees An Introduction into the Studies of the Natural History and Economy of the Bees Indigenous to the British Isles
Shuckard, William Edward
718 Gutenberg downloadsen2017Difficulty 72 (Expert)
Animal Castration
Liautard, Alexandre François Augustin
717 Gutenberg downloadsen2019Difficulty 71 (Expert)
Grundriß der menschlichen Erblichkeitslehre und Rassenhygiene (1/2) Menschliche Erblichkeitslehre
Baur, Erwin & Fischer, Eugen & Lenz, Fritz
717 Gutenberg downloadsde2015
Grundzüge der Paläontologie (Paläozoologie). 2. Abteilung: Vertebrata.
Zittel, Karl Alfred von
717 Gutenberg downloadsde2025
Migration of Birds (1979)
Lincoln, Frederick Charles & Peterson, Steven R.
716 Gutenberg downloadsen2021Difficulty 68 (Academic)
Bird studies with a camera : $b with introductory chapters on the outfit and methods of the bird photographer
Chapman, Frank M. (Frank Michler)
715 Gutenberg downloadsen2025Difficulty 50 (College)
A Monograph on the Sub-class Cirripedia (Volume 1 of 2) The Lepadidae; Or, Pedunculated Cirripedes
Darwin, Charles
714 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Introduction to the Study of Palæontological Botany
Balfour, John Hutton
713 Gutenberg downloadsen2016Difficulty 55 (Graduate)
The Appendages, Anatomy, and Relationships of Trilobites
Raymond, Percy E. (Percy Edward)
713 Gutenberg downloadsen2012Difficulty 67 (Academic)
Grundzüge der Paläontologie (Paläozoologie). 1. Abteilung: Invertebrata.
Zittel, Karl Alfred von
710 Gutenberg downloadsde2023
History of Embalming and of Preparations in Anatomy, Pathology, and Natural History; Including an Account of a New Process for Embalming
Gannal, J.-N. (Jean-Nicolas)
709 Gutenberg downloadsen2015Difficulty 78 (Expert)
Buffon's Natural History. Volume 08 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
Buffon, Georges Louis Leclerc, comte de
708 Gutenberg downloadsen2014Difficulty 61 (Academic)
Recuerdos de mi vida (tomo 2 de 2)
Ramón y Cajal, Santiago
708 Gutenberg downloadses2019
Our Common Insects A Popular Account of the Insects of Our Fields, Forests, Gardens and Houses
Packard, A. S. (Alpheus Spring)
706 Gutenberg downloadsen2008Difficulty 53 (Graduate)
La simulación en la lucha por la vida
Ingenieros, José
705 Gutenberg downloadses2020
Fishing Grounds of the Gulf of Maine
Rich, Walter H. (Walter Herbert)
703 Gutenberg downloadsen2005Difficulty 57 (Graduate)
The Botanical Magazine, Vol. 10 Or, Flower-Garden Displayed
Curtis, William
702 Gutenberg downloadsen2020Difficulty 57 (Graduate)
Vestiges of the Natural History of Creation
Chambers, Robert
699 Gutenberg downloadsen2004Difficulty 66 (Academic)
Trees: A Woodland Notebook Containing Observations on Certain British and Exotic Trees
Maxwell, Herbert, Sir
698 Gutenberg downloadsen2012Difficulty 59 (Graduate)
Mendel's principles of heredity: A defence
Bateson, William & Mendel, Gregor
697 Gutenberg downloadsen2022Difficulty 55 (Graduate)
The Ohio naturalist, Vol. 1, No. 3, January, 1901
Ohio State University. Biological Club
697 Gutenberg downloadsen2023Difficulty 53 (Graduate)
Aphorisms and Reflections from the works of T. H. Huxley
Huxley, Thomas Henry
695 Gutenberg downloadsen2011Difficulty 59 (Graduate)
The Flea
Russell, Harold
694 Gutenberg downloadsen2014Difficulty 53 (Graduate)
The Life of an Insect being a history of the changes of insects from the egg to the perfect being.
Unknown
694 Gutenberg downloadsen2014Difficulty 62 (Academic)
The Variation of Animals and Plants under Domestication — Volume 2
Darwin, Charles
694 Gutenberg downloadsen2001Difficulty 72 (Expert)
Death and resurrection from the point of view of the cell-theory
Björklund, Gustaf
693 Gutenberg downloadsen2019Difficulty 58 (Graduate)
Time and Change
Burroughs, John
693 Gutenberg downloadsen2004Difficulty 54 (Graduate)
Essays of a Biologist
Huxley, Julian
692 Gutenberg downloadsen2021Difficulty 66 (Academic)
The human foot and the human hand
Humphry, George Murray, Sir
691 Gutenberg downloadsen2025Difficulty 48 (College)
Noteworthy Records of Bats From Nicaragua, with a Checklist of the Chiropteran Fauna of the Country
Jones, J. Knox & Smith, James Dale & Turner, Ronald W.
690 Gutenberg downloadsen2010Difficulty 56 (Graduate)
Mimicry in Butterflies
Punnett, Reginald Crundall
689 Gutenberg downloadsen2013Difficulty 62 (Academic)
Metapsychical Phenomena: Methods and Observations
Maxwell, J. (Joseph)
688 Gutenberg downloadsen2014Difficulty 60 (Graduate)
Scientific American Supplement, No. 388, June 9, 1883
Various
688 Gutenberg downloadsen2005Difficulty 56 (Graduate)
Scientific American Supplement, No. 520, December 19, 1885
Various
688 Gutenberg downloadsen2004Difficulty 56 (Graduate)
Stray Feathers From a Bird Man's Desk
Rand, Austin Loomer
688 Gutenberg downloadsen2021Difficulty 54 (Graduate)
The Butterfly Book A Popular Guide to a Knowledge of the Butterflies of North America
Holland, W. J. (William Jacob)
688 Gutenberg downloadsen2012Difficulty 55 (Graduate)
The Story of the Living Machine A Review of the Conclusions of Modern Biology in Regard to the Mechanism Which Controls the Phenomena of Living Activity
Conn, H. W. (Herbert William)
688 Gutenberg downloadsen2005Difficulty 58 (Graduate)
Die Cellularpathologie in ihrer Begründung auf physiologische und pathologische Gewebelehre
Virchow, Rudolf
687 Gutenberg downloadsde2014
The Birds of Australia, Vol. 2 of 7
Gould, John
687 Gutenberg downloadsen2019Difficulty 66 (Academic)
The Variation of Animals and Plants under Domestication — Volume 1
Darwin, Charles
687 Gutenberg downloadsen2001Difficulty 62 (Academic)
Rudiments of Conchology Intended as a familiar introduction to the science.
Venning, Mary Anne
685 Gutenberg downloadsen2015Difficulty 49 (College)
A mechanical and critical enquiry into the nature of hermaphrodites
Parsons, James
684 Gutenberg downloadsen2023Difficulty 62 (Academic)
Essays: Scientific, Political, & Speculative; Vol. 1 of 3 Library Edition (1891), Containing Seven Essays not before Republished, and Various other Additions.
Spencer, Herbert
684 Gutenberg downloadsen2009Difficulty 67 (Academic)
The Kingdom of Man
Lankester, E. Ray (Edwin Ray), Sir
684 Gutenberg downloadsen2019Difficulty 61 (Academic)
Text Book of Biology, Part 1: Vertebrata
Wells, H. G. (Herbert George)
683 Gutenberg downloadsen2007Difficulty 61 (Academic)
The Making of Species
Dewar, Douglas & Finn, Frank
682 Gutenberg downloadsen2013Difficulty 72 (Expert)
Chambers's Elementary Science Readers Book I
Various
681 Gutenberg downloadsen2006Difficulty 27 (Middle School)
Dinosaurs, with Special Reference to the American Museum Collections
Matthew, William Diller
680 Gutenberg downloadsen2006Difficulty 59 (Graduate)
Half Hours With Modern Scientists: Lectures and Essays
Huxley, Thomas Henry & Barker, George F. (George Frederick) & Cope, E. D. (Edward Drinker) & Stirling, James Hutchison & Tyndall, John
680 Gutenberg downloadsen2021Difficulty 66 (Academic)
Science in Arcady
Allen, Grant
680 Gutenberg downloadsen2005Difficulty 63 (Academic)
Versuche über Pflanzenhybriden
Mendel, Gregor
679 Gutenberg downloadsde2012
The romance of the animal world : $b Interesting descriptions of the strange & curious in natural history
Selous, Edmund
677 Gutenberg downloadsen2023Difficulty 63 (Academic)
Homo-Culture; Or, The Improvement of Offspring Through Wiser Generation
Holbrook, M. L. (Martin Luther)
676 Gutenberg downloadsen2010Difficulty 66 (Academic)
How to Know the Ferns
Bastin, S. Leonard
676 Gutenberg downloadsen2014Difficulty 50 (College)
Every Girl's Book
Butler, George Frank
673 Gutenberg downloadsen2009Difficulty 41 (College)
The works of Francis Maitland Balfour, Volume 4 (of 4) : $b Plates
Balfour, Francis M. (Francis Maitland)
673 Gutenberg downloadsen2014Difficulty 50 (College)
L'Afrique centrale française : $b Récit du voyage de la mission
Chevalier, Auguste & Mission Chari-Lac Tchad (1902-1904)
669 Gutenberg downloadsfr2025
Animal Life in Field and Garden
Fabre, Jean-Henri
667 Gutenberg downloadsen2021Difficulty 47 (College)
Beginners' botany
Bailey, L. H. (Liberty Hyde)
666 Gutenberg downloadsen2024Difficulty 50 (College)
Man's Place in the Universe A Study of the Results of Scientific Research in Relation to the Unity or Plurality of Worlds, 3rd Edition
Wallace, Alfred Russel
666 Gutenberg downloadsen2012Difficulty 71 (Expert)
Synopsis of Some Genera of the Large Pyrenomycetes Camillea, Thamnomyces, Engleromyces
Lloyd, C. G. (Curtis Gates)
665 Gutenberg downloadsen2007Difficulty 52 (Graduate)
A Hand-book to the Primates, Volume 2 (of 2)
Forbes, Henry O. (Henry Ogg)
662 Gutenberg downloadsen2013Difficulty 54 (Graduate)
L'Académie des sciences et les académiciens de 1666 à 1793
Bertrand, Joseph
660 Gutenberg downloadsfr2016
Studies on Fermentation The diseases of beer, their causes, and the means of preventing them
Pasteur, Louis
659 Gutenberg downloadsen2020Difficulty 55 (Graduate)
The Mechanism of Life
Leduc, Stéphane
659 Gutenberg downloadsen2010Difficulty 63 (Academic)
Vertebrates from the Barrier Island of Tamaulipas, México
Selander, Robert K. & Johnston, Richard F. & Raun, Gerald G. & Wilks, B. J.
658 Gutenberg downloadsen2011Difficulty 54 (Graduate)
The Nests and Eggs of Indian Birds, Volume 1
Hume, Allan Octavian
657 Gutenberg downloadsen2004Difficulty 49 (College)
An Experimental Translocation of the Eastern Timber Wolf
Weise, Thomas F. & Hook, Richard A. & Mech, L. David & Robinson, William Laughlin
656 Gutenberg downloadsen2011Difficulty 56 (Graduate)
Buffon's Natural History. Volume 10 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c
Buffon, Georges Louis Leclerc, comte de
656 Gutenberg downloadsen2014Difficulty 61 (Academic)
Carpet Beetles and Their Control
Back, E. A. (Ernest Adna)
655 Gutenberg downloadsen2019Difficulty 55 (Graduate)
Elements of Physiophilosophy
Oken, Lorenz
655 Gutenberg downloadsen2015Difficulty 61 (Academic)
Fear
Mosso, A. (Angelo)
654 Gutenberg downloadsen2019Difficulty 59 (Graduate)
Scientific American Supplement, No. 561, October 2, 1886
Various
654 Gutenberg downloadsen2005Difficulty 50 (College)
Darwiniana : Essays — Volume 02
Huxley, Thomas Henry
653 Gutenberg downloadsen2004Difficulty 68 (Academic)
On the phenomena of hybridity in the genus Homo
Broca, Paul
653 Gutenberg downloadsen2014Difficulty 66 (Academic)
Zoological Illustrations, Second Series, Volume 2 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
653 Gutenberg downloadsen2013Difficulty 60 (Graduate)
The Lights of the Church and the Light of Science Essay #6 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
650 Gutenberg downloadsen2001Difficulty 70 (Academic)
The zoology of the voyage of H.M.S. Beagle [vol. 1 of 5] : $b Fossil mammalia
Owen, Richard
650 Gutenberg downloadsen2022Difficulty 58 (Graduate)
De afstamming van den mensch en de seksueele teeltkeus, deel 1 (van 2)
Darwin, Charles
649 Gutenberg downloadsnl2022
Scientific American Supplement, No. 711, August 17, 1889
Various
649 Gutenberg downloadsen2005Difficulty 61 (Academic)
Antarctic Penguins: A Study of Their Social Habits
Levick, G. Murray (George Murray)
648 Gutenberg downloadsen2011Difficulty 50 (College)
Memoir on the Dodo (Didus ineptus, Linn.)
Owen, Richard
648 Gutenberg downloadsen2025Difficulty 57 (Graduate)
Section Cutting and Staining A practical introduction to histological methods for students and practitioners
Colman, Walter S.
648 Gutenberg downloadsen2016Difficulty 50 (College)
The Coming of Evolution: The Story of a Great Revolution in Science
Judd, John W. (John Wesley)
648 Gutenberg downloadsen2010Difficulty 68 (Academic)
The Dwelling House
Poore, George Vivian
648 Gutenberg downloadsen2015Difficulty 52 (Graduate)
The Glands Regulating Personality A Study of the Glands of Internal Secretion in Relation to the Types of Human Nature
Berman, Louis
647 Gutenberg downloadsen2003Difficulty 58 (Graduate)
The honey-bee: its nature, homes and products
Harris, William Hetherington
647 Gutenberg downloadsen2022Difficulty 56 (Graduate)
The Brain and the Voice in Speech and Song
Mott, F. W. (Frederick Walker)
646 Gutenberg downloadsen2004Difficulty 68 (Academic)
The World's Greatest Books — Volume 15 — Science
Unknown
646 Gutenberg downloadsen2008Difficulty 67 (Academic)
Noteworthy families (modern science) : $b An index to kinships in near degrees between persons whose achievements are honourable, and have been publicly recorded
Galton, Francis & Schuster, Edgar
645 Gutenberg downloadsen2005Difficulty 64 (Academic)
On the Relations of Man to the Lower Animals
Huxley, Thomas Henry
645 Gutenberg downloadsen2001Difficulty 72 (Expert)
The octopus : $b or, The "devil-fish" of fiction and of fact
Lee, Henry
645 Gutenberg downloadsen2023Difficulty 61 (Academic)
Scientific American Supplement, No. 492, June 6, 1885
Various
644 Gutenberg downloadsen2004Difficulty 53 (Graduate)
Agricultural zoology
Ritzema Bos, J. (Jan)
643 Gutenberg downloadsen2025Difficulty 52 (Graduate)
Some Common Birds Useful to the Farmer (1915 edition)
Beal, F. E. L. (Foster Ellenborough Lascelles)
642 Gutenberg downloadsen2020Difficulty 54 (Graduate)
Life History and Ecology of the Five-Lined Skink, Eumeces fasciatus
Fitch, Henry S. (Henry Sheldon)
641 Gutenberg downloadsen2012Difficulty 62 (Academic)
American Addresses, with a Lecture on the Study of Biology
Huxley, Thomas Henry
640 Gutenberg downloadsen2005Difficulty 67 (Academic)
Spiders
Warburton, Cecil
639 Gutenberg downloadsen2013Difficulty 54 (Graduate)
Birds' Nests, Eggs and Egg-Collecting
Kearton, Richard
637 Gutenberg downloadsen2014Difficulty 65 (Academic)
The Dolphin in History
Montagu, Ashley & Lilly, John Cunningham
637 Gutenberg downloadsen2019Difficulty 56 (Graduate)
Scientific American Supplement No. 822, October 3, 1891
Various
636 Gutenberg downloadsen2005Difficulty 55 (Graduate)
A Guide for the Study of Animals
Whitney, Worrallo & Lucas, Frederic Colby & Shinn, Harold Brough & Smallwood, Mabel Elizabeth
634 Gutenberg downloadsen2011Difficulty 48 (College)
Dactylography; Or, The Study of Finger-prints
Faulds, Henry
634 Gutenberg downloadsen2015Difficulty 59 (Graduate)
General Anatomy, Applied to Physiology and Medicine, Vol. 3 (of 3)
Bichat, Xavier
634 Gutenberg downloadsen2018Difficulty 61 (Academic)
North American Jumping Mice (Genus Zapus)
Krutzsch, Philip H. (Philip Henry)
633 Gutenberg downloadsen2012Difficulty 64 (Academic)
Radioisotopes and Life Processes (Revised)
Kisieleski, Walter E. & Baserga, Renato
633 Gutenberg downloadsen2015Difficulty 66 (Academic)
The Popular Science Monthly, September, 1900 Vol. 57, May, 1900 to October, 1900
Various
632 Gutenberg downloadsen2014Difficulty 77 (Expert)
The Evolutionist at Large
Allen, Grant
630 Gutenberg downloadsen2014Difficulty 55 (Graduate)
The Meaning of Evolution
Schmucker, Samuel Christian
630 Gutenberg downloadsen2009Difficulty 51 (Graduate)
Roses: or, a Monograph of the Genus Rosa
Andrews, Henry Cranke, active 1799-1828
629 Gutenberg downloadsen2021Difficulty 63 (Academic)
Buffon's Natural History, Volume 03 (of 10) Containing a Theory of the Earth, a General History of Man, of the Brute Creation, and of Vegetables, Minerals, &c. &c.
Buffon, Georges Louis Leclerc, comte de
628 Gutenberg downloadsen2014Difficulty 68 (Academic)
Charles Darwin
Allen, Grant
628 Gutenberg downloadsen2010Difficulty 73 (Expert)
Species Plantarum, Sections I-III
Linné, Carl von
628 Gutenberg downloadsla2007
The ethics of Hercules : $b A study of man's body as the sole determinant of ethical values
Givler, Robert Chenault
628 Gutenberg downloadsen2023Difficulty 63 (Academic)
The flowering plants of South Africa; vol. 2
Unknown
628 Gutenberg downloadsen2021Difficulty 51 (Graduate)
Appletons' Popular Science Monthly, March 1900 Vol. 56, Nov. 1899 to April, 1900
Various
627 Gutenberg downloadsen2014Difficulty 55 (Graduate)
Le monde de la mer
Moquin-Tandon, Alfred
627 Gutenberg downloadsfr2023
Scientific American Supplement, No. 795, March 28, 1891
Various
627 Gutenberg downloadsen2004Difficulty 62 (Academic)
The Foot-prints of the Creator : $b or, The Asterolepis of Stromness
Miller, Hugh
627 Gutenberg downloadsen2022Difficulty 66 (Academic)
Heroes of science : $b Botanists, zoologists, and geologists
Duncan, P. Martin (Peter Martin)
626 Gutenberg downloadsen2023Difficulty 58 (Graduate)
The History of Insects
Unknown
626 Gutenberg downloadsen2004Difficulty 55 (Graduate)
The honey bee: a manual of instruction in apiculture
Benton, Frank
626 Gutenberg downloadsen2022Difficulty 55 (Graduate)
The Migration of North American Birds (1935)
Lincoln, Frederick Charles
626 Gutenberg downloadsen2021Difficulty 71 (Expert)
The pathology of influenza
Winternitz, M. C. (Milton C.) & McNamara, Frank P. & Wason, Isabel M.
625 Gutenberg downloadsen2019Difficulty 69 (Academic)
Creierul, O Enigma Descifrata
Moisa, Dorin Teodor
624 Gutenberg downloadsro2004
On the Origin and Metamorphoses of Insects
Lubbock, John, Sir
622 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Ants and Some Other Insects: An Inquiry Into the Psychic Powers of These Animals
Forel, Auguste
621 Gutenberg downloadsen2016Difficulty 70 (Academic)
The Interpreters of Genesis and the Interpreters of Nature Essay #4 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
621 Gutenberg downloadsen2001Difficulty 65 (Academic)
De Canibus Britannicis: Of Englishe Dogges
Caius, John
619 Gutenberg downloadsen2008Difficulty 81 (Specialist)
The Origin of Species From 'The Westminster Review', April 1860
Huxley, Thomas Henry
619 Gutenberg downloadsen2001Difficulty 74 (Expert)
A Synopsis of the Birds of North America
Audubon, John James
618 Gutenberg downloadsen2013Difficulty 50 (College)
Appletons' Popular Science Monthly, February 1900 Vol. 56, November, 1899 to April, 1900
Various
618 Gutenberg downloadsen2014Difficulty 62 (Academic)
Scientific American Supplement, No. 433, April 19, 1884
Various
618 Gutenberg downloadsen2005Difficulty 66 (Academic)
Wood and Forest
Noyes, William
618 Gutenberg downloadsen2011Difficulty 51 (Graduate)
The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee
Gray, Asa
617 Gutenberg downloadsen2012Difficulty 60 (Graduate)
The Mason-Wasps
Fabre, Jean-Henri
617 Gutenberg downloadsen2021Difficulty 50 (College)
The Popular Science Monthly, July, 1900 Vol. 57, May, 1900 to October, 1900
Various
617 Gutenberg downloadsen2014Difficulty 56 (Graduate)
Natural Wonders
Brewster, Edwin Tenney
616 Gutenberg downloadsen2015Difficulty 40 (High School)
Scientific American Supplement, No. 363, December 16, 1882
Various
615 Gutenberg downloadsen2005Difficulty 62 (Academic)
Seed Dispersal
Beal, W. J. (William James)
615 Gutenberg downloadsen2008Difficulty 46 (College)
The horse's mouth, showing the age by the teeth
Mayhew, Edward
615 Gutenberg downloadsen2014Difficulty 55 (Graduate)
Harvey's Views on the Use of the Circulation of the Blood
Curtis, John Green
614 Gutenberg downloadsen2014Difficulty 69 (Academic)
Scientific American Supplement, No. 810, July 11, 1891
Various
614 Gutenberg downloadsen2005Difficulty 51 (Graduate)
The Vivisectors' Directory Being a list of the licensed vivisectors in the United Kingdom, together with the leading physiologists in foreign laboratories
Unknown
614 Gutenberg downloadsen2017Difficulty 61 (Academic)
Mendelism Third Edition
Punnett, Reginald Crundall
613 Gutenberg downloadsen2009Difficulty 61 (Academic)
Through Magic Glasses and Other Lectures A Sequel to The Fairyland of Science
Buckley, Arabella B. (Arabella Burton)
613 Gutenberg downloadsen2011Difficulty 58 (Graduate)
Fossil Butterflies Memoirs of the American Association for the Advancement of Science, I.
Scudder, Samuel Hubbard
612 Gutenberg downloadsen2017Difficulty 59 (Graduate)
Introduction à l'étude de la médecine expérimentale
Bernard, Claude
612 Gutenberg downloadsfr2005
The preparation & mounting of microscopic objects
Davies, Thomas
612 Gutenberg downloadsen2019Difficulty 53 (Graduate)
Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, I. Band Von den Anfängen bis zum Wiederaufleben der Wissenschaften
Dannemann, Friedrich
610 Gutenberg downloadsde2016
The Kansas University Quarterly, Vol. I, No. 1 (1892)
Various
610 Gutenberg downloadsen2017Difficulty 58 (Graduate)
The Present Condition of Organic Nature Lecture I. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
610 Gutenberg downloadsen2001Difficulty 64 (Academic)
Life History of the Kangaroo Rat
Vorhies, Charles Taylor & Taylor, Walter P. (Walter Penn)
609 Gutenberg downloadsen2006Difficulty 62 (Academic)
Ancient Plants Being a Simple Account of the past Vegetation of the Earth and of the Recent Important Discoveries Made in This Realm of Nature
Stopes, Marie Carmichael
608 Gutenberg downloadsen2013Difficulty 57 (Graduate)
Het Leven der Dieren: Deel 2, Hoofdstuk 04: De Hoendervogels
Brehm, Alfred Edmund
608 Gutenberg downloadsnl2009
On Some Fossil Remains of Man
Huxley, Thomas Henry
608 Gutenberg downloadsen2001Difficulty 60 (Graduate)
The Evolution of Man Scientifically Disproved in 50 Arguments
Williams, William A. (William Asbury)
608 Gutenberg downloadsen2005Difficulty 55 (Graduate)
The Biology, Physiology and Sociology of Reproduction Also Sexual Hygiene with Special Reference to the Male
Hall, Winfield Scott
607 Gutenberg downloadsen2008Difficulty 56 (Graduate)
Flora von Deutschland Ein Hilfsbuch zum Bestimmen der zwischen den deutschen Meeren und den Alpen wildwachsenden und angebauten Pflanzen
Schmeil, O. (Otto) & Fitschen, Jost
606 Gutenberg downloadsde2019
The Book of Love
Mantegazza, Paolo
606 Gutenberg downloadsen2018Difficulty 72 (Expert)
Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, II. Band Von Galilei bis zur Mitte des XVIII. Jahrhunderts
Dannemann, Friedrich
602 Gutenberg downloadsde2017
Chambers's Journal of Popular Literature, Science, and Art, No. 683 January 27, 1877
Various
601 Gutenberg downloadsen2014Difficulty 50 (College)
Life of Elie Metchnikoff, 1845-1916
Metchnikoff, Olga
601 Gutenberg downloadsen2013Difficulty 66 (Academic)
Ideen zu einer Physiognomik der Gewächse
Humboldt, Alexander von
600 Gutenberg downloadsde2007
Thoughts on Religion
Romanes, George John
600 Gutenberg downloadsen2005Difficulty 72 (Expert)
The Bird Study Book
Pearson, T. Gilbert (Thomas Gilbert)
599 Gutenberg downloadsen2007Difficulty 52 (Graduate)
The Structure and Habits of Spiders
Emerton, J. H. (James Henry)
599 Gutenberg downloadsen2018Difficulty 44 (College)
Natural History of the Ornate Box Turtle, Terrapene ornata ornata Agassiz
Legler, John M.
598 Gutenberg downloadsen2011Difficulty 63 (Academic)
Het Leven der Dieren. Deel 3. Afdeling 2. De Visschen
Brehm, Alfred Edmund
597 Gutenberg downloadsnl2016
Life Movements in Plants, Volume II
Bose, Jagadis Chandra
597 Gutenberg downloadsen2012Difficulty 73 (Expert)
Little Masterpieces of Science: The Naturalist as Interpreter and Seer
Unknown
597 Gutenberg downloadsen2009Difficulty 63 (Academic)
Report on the Migration of Birds in the Spring and Autumn of 1886. Eighth Report (Vol. II, No. 3.)
Harvie-Brown, J. A. (John Alexander) & Barrington, Richard Manliffe & Clarke, William Eagle & Cordeaux, John & More, Alexander Goodman
597 Gutenberg downloadsen2021Difficulty 43 (College)
Birds in Flight
Pycraft, W. P. (William Plane)
596 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Grundriß der menschlichen Erblichkeitslehre und Rassenhygiene (2/2) Menschliche Auslese und Rassenhygiene
Lenz, Fritz
596 Gutenberg downloadsde2015
On the Advisableness of Improving Natural Knowledge
Huxley, Thomas Henry
596 Gutenberg downloadsen2001Difficulty 72 (Expert)
Evolution: Its nature, its evidence, and its relation to religious thought
LeConte, Joseph
595 Gutenberg downloadsen2014Difficulty 88 (Specialist)
Hints towards the formation of a more comprehensive theory of life.
Coleridge, Samuel Taylor
595 Gutenberg downloadsen2008Difficulty 68 (Academic)
Identifying Hardwoods Growing on Pine Sites
Brown, Clair A. (Clair Alan) & Grelen, Harold E.
595 Gutenberg downloadsen2021Difficulty 54 (Graduate)
Scientific American Supplement, No. 601, July 9, 1887
Various
594 Gutenberg downloadsen2004Difficulty 53 (Graduate)
Facts and Arguments for Darwin
Müller, Fritz
593 Gutenberg downloadsen2004Difficulty 70 (Academic)
Little Masterpieces of Science: Health and Healing
Unknown
593 Gutenberg downloadsen2014Difficulty 53 (Graduate)
Physics and Politics, or, Thoughts on the application of the principles of "natural selection" and "inheritance" to political society
Bagehot, Walter
593 Gutenberg downloadsen2003Difficulty 64 (Academic)
Life: Its True Genesis
Flaccus, Horatius
592 Gutenberg downloadsen2005Difficulty 60 (Graduate)
Disease and Its Causes
Councilman, W. T. (William Thomas)
591 Gutenberg downloadsen2005Difficulty 57 (Graduate)
Subspeciation in the Kangaroo Rat, Dipodomys ordii KU. Vol 1 No 23
Setzer, Henry W.
591 Gutenberg downloadsen2013Difficulty 66 (Academic)
The Child's Book of Nature Three parts in one
Hooker, Worthington
591 Gutenberg downloadsen2018Difficulty 36 (High School)
Les abeilles
Pérez, Jean M.
590 Gutenberg downloadsfr2011
North American Yellow Bats, 'Dasypterus,' and a List of the Named Kinds of the Genus Lasiurus Gray
Hall, E. Raymond (Eugene Raymond) & Jones, J. Knox
589 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Die Welträtsel: Gemeinverständliche Studien über Monistische Philosophie
Haeckel, Ernst
588 Gutenberg downloadsde2019
Outlines of Lessons in Botany, Part I; from Seed to Leaf For the Use of Teachers, or Mothers Studying with Their Children
Moore, Jane Newell
588 Gutenberg downloadsen2004Difficulty 42 (College)
The Rise and Progress of Palaeontology Essay #2 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
587 Gutenberg downloadsen2001Difficulty 77 (Expert)
The Botanist's Companion, Volume II Or an Introduction to the Knowledge of Practical Botany, and the Uses of Plants. Either Growing Wild in Great Britain, or Cultivated for the Puroses of Agriculture, Medicine, Rural Oeconomy, or the Arts
Salisbury, William
586 Gutenberg downloadsen2004Difficulty 55 (Graduate)
Popular Books on Natural Science For Practical Use in Every Household, for Readers of All Classes
Bernstein, Aaron David
584 Gutenberg downloadsen2011Difficulty 50 (College)
Speciation in the Brazilian Spiny Rats
Moojen, João
584 Gutenberg downloadsen2013Difficulty 70 (Academic)
Het Leven der Dieren. Derde Deel, Hoofdstuk 1 tot 4, De Kruipende Dieren
Brehm, Alfred Edmund
583 Gutenberg downloadsnl2014
Mazedonien : $b Erlebnisse und Beobachtungen eines Naturforschers im Gefolge des deutschen Heeres
Doflein, Franz
583 Gutenberg downloadsde2023
The Philosophy of Health; Volume 2 (of 2) or, an exposition of the physical and mental constitution of man
Smith, Southwood
583 Gutenberg downloadsen2019Difficulty 72 (Expert)
Creation and Its Records A Brief Statement of Christian Belief with Reference to Modern Facts and Ancient Scripture
Baden-Powell, B. H. (Baden Henry)
582 Gutenberg downloadsen2004Difficulty 62 (Academic)
Lehrbuch der Toxikologie für Tierärzte
Fröhner, Eugen
581 Gutenberg downloadsde2022
Natural History of the Racer Coluber constrictor
Fitch, Henry S. (Henry Sheldon)
581 Gutenberg downloadsen2013Difficulty 69 (Academic)
Poisonous Snakes of Texas and First Aid Treatment of Their Bites Bulletin No. 31
Werler, John E.
581 Gutenberg downloadsen2017Difficulty 58 (Graduate)
Studies in the Theory of Descent (Volumes 1 and 2)
Weismann, August
581 Gutenberg downloadsen2015Difficulty 68 (Academic)
Scientific American Supplement, No. 417, December 29, 1883
Various
579 Gutenberg downloadsen2005Difficulty 65 (Academic)
Essays in eugenics
Galton, Francis
578 Gutenberg downloadsen2024Difficulty 59 (Graduate)
Scientific American Supplement, No. 299, September 24, 1881
Various
578 Gutenberg downloadsen2005Difficulty 60 (Graduate)
British Sea Birds
Dixon, Charles
577 Gutenberg downloadsen2014Difficulty 61 (Academic)
The Principles of Breeding or, Glimpses at the Physiological Laws involved in the Reproduction and Improvement of Domestic Animals
Goodale, S. L. (Stephen Lincoln)
577 Gutenberg downloadsen2007Difficulty 57 (Graduate)
Birds, Illustrated by Color Photography, Vol. 1, No. 6 June, 1897
Various
575 Gutenberg downloadsen2009Difficulty 48 (College)
Duality of Voice
Sutro, Emil
575 Gutenberg downloadsen2015Difficulty 63 (Academic)
The Atom and the Ocean
Hull, E. W. Seabrook
575 Gutenberg downloadsen2021Difficulty 61 (Academic)
The Birds of Australia, Vol. 3 of 7
Gould, John
574 Gutenberg downloadsen2019Difficulty 61 (Academic)
Über die Entstehung der Arten im Thier- und Pflanzen-Reich durch natürliche Züchtung
Darwin, Charles
574 Gutenberg downloadsde2022
Zoological Illustrations, Second Series, Volume 1 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
573 Gutenberg downloadsen2013Difficulty 59 (Graduate)
Physiological Researches on Life and Death
Bichat, Xavier
572 Gutenberg downloadsen2018Difficulty 60 (Graduate)
The Botanical Magazine, Vol. 07 Or, Flower-Garden Displayed
Curtis, William
572 Gutenberg downloadsen2007Difficulty 58 (Graduate)
The Edinburgh New Philosophical Journal, Vol. XLIX April-October 1850
Various
572 Gutenberg downloadsen2013Difficulty 66 (Academic)
Scientific American Supplement, No. 315, January 14, 1882
Various
571 Gutenberg downloadsen2006Difficulty 63 (Academic)
Forest Trees of Illinois: How to Know Them
Fuller, George D. (George Damon) & Mattoon, Wilbur R. (Wilbur Reed) & Miller, Robert B. (Robert Barclay) & Nuuttila, E. E.
570 Gutenberg downloadsen2011Difficulty 50 (College)
Canterbury Pieces
Butler, Samuel
569 Gutenberg downloadsen2002Difficulty 55 (Graduate)
European Fungus Flora: Agaricaceae
Massee, George
569 Gutenberg downloadsen2010Difficulty 48 (College)
Warum wir sterben
Lipschütz, Alejandro
568 Gutenberg downloadsde2008
From an Easy Chair
Lankester, E. Ray (Edwin Ray), Sir
566 Gutenberg downloadsen2020Difficulty 50 (College)
Mr. Gladstone and Genesis Essay #5 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
566 Gutenberg downloadsen2001Difficulty 59 (Graduate)
Scientific American Supplement, No. 829, November 21, 1891
Various
566 Gutenberg downloadsen2005Difficulty 63 (Academic)
De l'origine des espèces
Darwin, Charles
565 Gutenberg downloadsfr2004
Scientific American Supplement, No. 324, March 18, 1882
Various
565 Gutenberg downloadsen2005Difficulty 53 (Graduate)
The Popular Science Monthly, August, 1900 Vol. 57, May, 1900 to October, 1900
Various
565 Gutenberg downloadsen2014Difficulty 68 (Academic)
Within the Deep Cassell's "Eyes and No Eyes" Series, Book VIII.
Smith, R. Cadwallader
565 Gutenberg downloadsen2004Difficulty 34 (High School)
A Critical Examination of the Position of Mr. Darwin's Work, "On the Origin of Species," in Relation to the Complete Theory of the Causes of the Phenomena of Organic Nature Lecture VI. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
564 Gutenberg downloadsen2001Difficulty 67 (Academic)
The Toxicity of Caffein: An experimental study on different species of animals
Salant, William & Rieger, J. B. (John Benjamin)
564 Gutenberg downloadsen2014Difficulty 63 (Academic)
A Guide for the Dissection of the Dogfish (Squalus Acanthias)
Griffin, Lawrence Edmonds
563 Gutenberg downloadsen2019Difficulty 54 (Graduate)
Die epiphytische Vegetation Amerikas
Schimper, A. F. W. (Andreas Franz Wilhelm)
563 Gutenberg downloadsde2007
On the Study of Zoology
Huxley, Thomas Henry
563 Gutenberg downloadsen2001Difficulty 66 (Academic)
Birds of Guernsey (1879) And the Neighbouring Islands: Alderney, Sark, Jethou, Herm; Being a Small Contribution to the Ornitholony of the Channel Islands
Smith, Cecil
562 Gutenberg downloadsen2004Difficulty 65 (Academic)
Scientific American Supplement, No. 595, May 28, 1887
Various
562 Gutenberg downloadsen2004Difficulty 52 (Graduate)
A Synopsis of Neotropical Hylid Frogs, Genus Osteocephalus
Trueb, Linda & Duellman, William Edward
561 Gutenberg downloadsen2011Difficulty 67 (Academic)
Ameboid movement
Schaeffer, Asa A. (Asa Arthur)
561 Gutenberg downloadsen2017Difficulty 66 (Academic)
Nouveaux souvenirs entomologiques - Livre II Étude sur l'instinct et les moeurs des insectes
Fabre, Jean-Henri
561 Gutenberg downloadsfr2006
Scientific American Supplement, No. 303, October 22, 1881
Various
561 Gutenberg downloadsen2005Difficulty 52 (Graduate)
Atoms, Nature, and Man: Man-made Radioactivity in the Environment
Hines, Neal O.
560 Gutenberg downloadsen2015Difficulty 68 (Academic)
Report on the Migration of Birds in the Spring and Autumn of 1883. Fifth Report
Harvie-Brown, J. A. (John Alexander) & Barrington, Richard Manliffe & Cordeaux, John & More, Alexander Goodman
560 Gutenberg downloadsen2021Difficulty 44 (College)
Scientific American Supplement, No. 358, November 11, 1882
Various
560 Gutenberg downloadsen2005Difficulty 61 (Academic)
Outlines of dairy bacteriology, 10th edition A concise manual for the use of students in dairying
Russell, H. L. (Harry Luman) & Hastings, E. G. (Edwin George)
559 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Poisonous Dwellers of the Desert
Dodge, Natt N. (Natt Noyes)
559 Gutenberg downloadsen2017Difficulty 61 (Academic)
Scientific American Supplement, No. 441, June 14, 1884.
Various
559 Gutenberg downloadsen2005Difficulty 56 (Graduate)
On the Reception of the 'Origin of Species'
Huxley, Thomas Henry
558 Gutenberg downloadsen2000Difficulty 66 (Academic)
British birds
Hudson, W. H. (William Henry) & Beddard, Frank E. (Frank Evers)
557 Gutenberg downloadsen2024Difficulty 67 (Academic)
The Botanical Magazine, Vol. 05 Or, Flower-Garden Displayed
Curtis, William
557 Gutenberg downloadsen2006Difficulty 57 (Graduate)
A Critique of the Theory of Evolution
Morgan, Thomas Hunt
556 Gutenberg downloadsen2009Difficulty 57 (Graduate)
British Butterflies: Figures and Descriptions of Every Native Species
Coleman, W. S. (William Stephen)
556 Gutenberg downloadsen2010Difficulty 65 (Academic)
The Adductor Muscles of the Jaw In Some Primitive Reptiles
Fox, Richard C.
556 Gutenberg downloadsen2009Difficulty 66 (Academic)
Het Leven der Dieren, Deel 3, Hoofdstuk 04: De Insecten
Brehm, Alfred Edmund
555 Gutenberg downloadsnl2020
Nouvel atlas de poche des champignons Comestibles et Vénéneux les plus répandus. Série II (Première édition)
Dumée, Paul
555 Gutenberg downloadsfr2017
Scientific American Supplement, No. 455, September 20, 1884
Various
554 Gutenberg downloadsen2004Difficulty 57 (Graduate)
The flowering plants of South Africa; vol. 4
Pole Evans, I. B. (Illtyd Buller)
554 Gutenberg downloadsen2023Difficulty 49 (College)
Race Improvement; or, Eugenics: A Little Book on a Great Subject
Baker, La Reine Helen McKenzie
553 Gutenberg downloadsen2015Difficulty 63 (Academic)
Studies on Epidemic Influenza: Comprising Clinical and Laboratory Investigations
University of Pittsburgh. School of Medicine
553 Gutenberg downloadsen2019Difficulty 62 (Academic)
The Social Direction of Evolution: An Outline of the Science of Eugenics
Kellicott, William E. (William Erskine)
552 Gutenberg downloadsen2010Difficulty 63 (Academic)
Experiments and Observations Relative to the Influence Lately Discovered by M. Galvani and Commonly Called Animal Electricity
Fowler, Richard
551 Gutenberg downloadsen2014Difficulty 64 (Academic)
Scientific American Supplement, No. 643, April 28, 1888
Various
551 Gutenberg downloadsen2005Difficulty 65 (Academic)
Venomous arthropod handbook : $b envenomization symptoms/treatment, identification, biology and control
Biery, Terry L.
549 Gutenberg downloadsen2018Difficulty 66 (Academic)
Scientific American Supplement, No. 385, May 19, 1883
Various
548 Gutenberg downloadsen2005Difficulty 58 (Graduate)
Histology of the Blood, Normal and Pathological
Ehrlich, Paul & Lazarus, Adolf
546 Gutenberg downloadsen2009Difficulty 63 (Academic)
The Pecan and its Culture
Hume, H. Harold (Hardrada Harold)
546 Gutenberg downloadsen2009Difficulty 57 (Graduate)
Scientific American Supplement, No. 613, October 1, 1887
Various
545 Gutenberg downloadsen2005Difficulty 63 (Academic)
Appletons' Popular Science Monthly, November 1898 Volume 54, November 1898
Various
544 Gutenberg downloadsen2013Difficulty 60 (Graduate)
Darwiniana; Essays and Reviews Pertaining to Darwinism
Gray, Asa
544 Gutenberg downloadsen2004Difficulty 69 (Academic)
The Past Condition of Organic Nature Lecture II. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
543 Gutenberg downloadsen2001Difficulty 65 (Academic)
The Underworld of Oregon Caves National Monument
Contor, Roger J.
542 Gutenberg downloadsen2019Difficulty 56 (Graduate)
A Review of the Middle American Tree Frogs of the Genus Ptychohyla
Duellman, William Edward
541 Gutenberg downloadsen2011Difficulty 58 (Graduate)
Life among the butterflies
Randolph, Vance
541 Gutenberg downloadsen2022Difficulty 56 (Graduate)
Summer Birds From the Yucatan Peninsula, Mexico
Klaas, Erwin E.
541 Gutenberg downloadsen2011Difficulty 52 (Graduate)
Himalayan Journals — Volume 1 Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.
Hooker, Joseph Dalton
539 Gutenberg downloadsen2004Difficulty 74 (Expert)
On the Method of Zadig Essay #1 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
539 Gutenberg downloadsen2001Difficulty 66 (Academic)
The botanist's repository for new and rare plants; vol. 06 [of 10]
Andrews, Henry Cranke, active 1799-1828
539 Gutenberg downloadsen2024Difficulty 63 (Academic)
The Conditions of Existence as Affecting the Perpetuation of Living Beings Lecture V. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
539 Gutenberg downloadsen2001Difficulty 64 (Academic)
Yeast
Huxley, Thomas Henry
539 Gutenberg downloadsen2001Difficulty 66 (Academic)
Dr. B. Mure's materia medica : $b or, provings of the principal animal and vegetable poisons of the Brazilian Empire, and their application in the treatment of disease
Mure, Benoît
538 Gutenberg downloadsen2023Difficulty 45 (College)
Westafrikanische Kautschuk-Expedition
Schlechter, Rudolf & Deutsche Kolonialgesellschaft. Kolonial-Wirtschaftliches Komitee
538 Gutenberg downloadsde2022
A Treatise on Physiology and Hygiene For Educational Institutions and General Readers
Hutchison, Joseph C. (Joseph Chrisman)
537 Gutenberg downloadsen2010Difficulty 53 (Graduate)
On the Seashore Cassell's "Eyes and No Eyes" Series, Book VII
Smith, R. Cadwallader
537 Gutenberg downloadsen2003Difficulty 35 (High School)
Lectures on Evolution Essay #3 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
536 Gutenberg downloadsen2001Difficulty 69 (Academic)
Natural Philosophy
Ostwald, Wilhelm
536 Gutenberg downloadsen2013Difficulty 60 (Graduate)
Rede, gehalten bei der Eröffnung der Versammlung deutscher Naturforscher und Ärzte in Berlin, am 18. September 1828
Humboldt, Alexander von
536 Gutenberg downloadsde2007
The Elements of Agriculture A Book for Young Farmers, with Questions Prepared for the Use of Schools
Waring, George E. (George Edwin)
536 Gutenberg downloadsen2010Difficulty 53 (Graduate)
New observations on the natural history of bees
Huber, François
535 Gutenberg downloadsen2008Difficulty 57 (Graduate)
Scientific American Supplement, No. 275, April 9, 1881
Various
535 Gutenberg downloadsen2005Difficulty 57 (Graduate)
Arabische Pflanzennamen aus Aegypten, Algerien und Jemen
Schweinfurth, Georg August
534 Gutenberg downloadsde2024
Mammals of Northwestern South Dakota
Andersen, Kenneth W. & Jones, J. Knox
534 Gutenberg downloadsen2010Difficulty 50 (College)
Evolution and creation
Hardwicke, Herbert Junius
533 Gutenberg downloadsen2017Difficulty 64 (Academic)
Het paddenstoelenboekje
Cool, Cath. (Catharina) & Lek, H. A. A. van der (Hendrik Adrianus Abraham)
533 Gutenberg downloadsnl2015
Journal of Entomology and Zoology, Vol. 09, No. 3, September 1917
Various
533 Gutenberg downloadsen2015Difficulty 56 (Graduate)
Appletons' Popular Science Monthly, January 1899 Volume LIV, No. 3, January 1899
Various
532 Gutenberg downloadsen2013Difficulty 56 (Graduate)
Essays in Natural History and Agriculture
Garnett, Thomas
532 Gutenberg downloadsen2006Difficulty 64 (Academic)
The Botanical Magazine, Vol. 02 Or, Flower-Garden Displayed
Curtis, William
532 Gutenberg downloadsen2006Difficulty 57 (Graduate)
The genetic and the operative evidence relating to secondary sexual characters
Morgan, Thomas Hunt
532 Gutenberg downloadsen2018Difficulty 47 (College)
Beautiful Ferns
Eaton, Daniel Cady
531 Gutenberg downloadsen2014Difficulty 58 (Graduate)
The Method by Which the Causes of the Present and Past Conditions of Organic Nature Are to Be Discovered; the Origination of Living Beings Lecture III. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
531 Gutenberg downloadsen2001Difficulty 61 (Academic)
Was Man Created?
Mott, Henry A. (Henry Augustus)
531 Gutenberg downloadsen2009Difficulty 66 (Academic)
Geological Contemporaneity and Persistent Types of Life
Huxley, Thomas Henry
530 Gutenberg downloadsen2001Difficulty 72 (Expert)
Relics of Primeval Life: Beginning of Life in the Dawn of Geological Time
Dawson, John William, Sir
530 Gutenberg downloadsen2022Difficulty 58 (Graduate)
Middle American Frogs of the Hyla microcephala Group
Duellman, William Edward & Fouquette, M. J.
529 Gutenberg downloadsen2010Difficulty 66 (Academic)
The flowering plants of South Africa; vol. 5
Pole Evans, I. B. (Illtyd Buller)
529 Gutenberg downloadsen2025Difficulty 50 (College)
Biology versus Theology. The Bible: irreconcilable with Science, Experience, and even its own statements
Julian
528 Gutenberg downloadsen2021Difficulty 52 (Graduate)
De afstamming van den mensch en de seksueele teeltkeus, deel 2 (van 2)
Darwin, Charles
528 Gutenberg downloadsnl2024
Scientific American Supplement, No. 787, January 31, 1891
Various
528 Gutenberg downloadsen2004Difficulty 53 (Graduate)
The Mental Life of Monkeys and Apes: A Study of Ideational Behavior
Yerkes, Robert Mearns
528 Gutenberg downloadsen2004Difficulty 61 (Academic)
The Physical Basis of Mind Being the Second Series of Problems of Life and Mind.
Lewes, George Henry
528 Gutenberg downloadsen2019Difficulty 70 (Academic)
Die Tier- und Pflanzenwelt des Süsswassers. Erster Band.
Forel, F. A. (François Alphonse) & Gruber, August & Ludwig, Friedrich & Migula, W. (Walter) & Plate, Ludwig & Vosseler, Julius & Weltner, Wilhelm
527 Gutenberg downloadsde2024
Supplement to the catalogue of seals and whales in the British Museum
Gray, John Edward
527 Gutenberg downloadsen2023Difficulty 45 (College)
The zoology of the voyage of H.M.S. Beagle [vol. 3 of 5] : $b Birds
Gould, John
527 Gutenberg downloadsen2024Difficulty 54 (Graduate)
The Conchologist's First Book A System of Testaceous Malacology, Arranged Expressly for the Use of Schools, in Which the Animals, According to Cuvier, Are Given With the Shells, a Great Number of New Species Added, and the Whole Brought Up, as Accurately as Possible, to the Present Condition of the Science.
Poe, Edgar Allan & Brown, Thomas
526 Gutenberg downloadsen2021Difficulty 53 (Graduate)
The Illustrated Self-Instructor in Phrenology and Physiology
Fowler, O. S. (Orson Squire) & Fowler, L. N. (Lorenzo Niles)
526 Gutenberg downloadsen2010Difficulty 64 (Academic)
The Minor Horrors of War
Shipley, A. E. (Arthur Everett), Sir
526 Gutenberg downloadsen2021Difficulty 51 (Graduate)
On Snake-Poison: Its Action and Its Antidote
Mueller, A.
525 Gutenberg downloadsen2010Difficulty 69 (Academic)
The Deseado Formation of Patagonia
Loomis, Frederic Brewster
525 Gutenberg downloadsen2024Difficulty 61 (Academic)
Whale Primer, with Special Attention to the California Gray Whale
Walker, Theodore J.
525 Gutenberg downloadsen2019Difficulty 55 (Graduate)
Μικρά Φυσικά, Τόμος Πρώτος
Aristotle
524 Gutenberg downloadsel2009
El Campesino Puertorriqueño Sus Condiciones Físicas, Intelectuales y Morales, Causas que la Determinan y Medios Para Mejorarlas
Valle Atiles, Francisco del
523 Gutenberg downloadses2015
The botanist's repository for new and rare plants; vol. 09 [of 10]
Andrews, Henry Cranke, active 1799-1828
523 Gutenberg downloadsen2024Difficulty 55 (Graduate)
Bog-trotting for orchids
Niles, Grace Greylock
522 Gutenberg downloadsen2025Difficulty 61 (Academic)
Die Tier- und Pflanzenwelt des Süsswassers. Zweiter Band.
Apstein, C. (Carl Heinrich) & Borcherding, Friedrich & Clessin, Stephan & Kramer, Paul & Schmidt-Schwedt, E. & Seligo, Arthur & Zschokke, Friedrich
522 Gutenberg downloadsde2024
Handbuch der Pharmakognosie : $b Zweiter Band. Spezielle Pharmakognosie
Tschirch, A. (Alexander)
522 Gutenberg downloadsde2023
Natur und Mensch Sechs Abschnitte aus Werken von Ernst Haeckel
Haeckel, Ernst
522 Gutenberg downloadsde2015
The Migration of Birds
Coward, T. A. (Thomas Alfred)
522 Gutenberg downloadsen2013Difficulty 67 (Academic)
On the cattle plague: or, Contagious typhus in horned cattle. Its history, origin, description, and treatment
Bourguignon, Honoré
521 Gutenberg downloadsen2011Difficulty 69 (Academic)
Scientific American Supplement, No. 344, August 5, 1882
Various
521 Gutenberg downloadsen2005Difficulty 54 (Graduate)
Himalayan Journals — Volume 2 Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.
Hooker, Joseph Dalton
520 Gutenberg downloadsen2004Difficulty 69 (Academic)
Evolution Social and Organic
Lewis, Arthur M. (Arthur Morrow)
519 Gutenberg downloadsen2018Difficulty 57 (Graduate)
Parasiten der Honigbiene und die durch dieselben bedingten Krankheiten dieses Insects.
Assmuss, Eduard Philibert
519 Gutenberg downloadsde2006
Species Plantarum, Sections VI-X
Linné, Carl von
519 Gutenberg downloadsla2009
Quadrupeds, What They Are and Where Found: A Book of Zoology for Boys
Reid, Mayne
518 Gutenberg downloadsen2007Difficulty 55 (Graduate)
Amphibians and Reptiles of the Rainforests of Southern El Petén, Guatemala
Duellman, William Edward
517 Gutenberg downloadsen2011Difficulty 64 (Academic)
A Distributional Study of the Amphibians of the Isthmus of Tehuantepec, México
Duellman, William Edward
516 Gutenberg downloadsen2011Difficulty 65 (Academic)
Dissection of the Platana and the Frog
Gilchrist, J. D. F. (John Dow Fisher) & Bonde, Cecil von
514 Gutenberg downloadsen2015Difficulty 51 (Graduate)
Bees
Phillips, Everett Franklin
513 Gutenberg downloadsen2015Difficulty 52 (Graduate)
Theory of circulation by respiration : $b synopsis of its principles and history
Willard, Emma
513 Gutenberg downloadsen2006Difficulty 57 (Graduate)
Last Words on Evolution: A Popular Retrospect and Summary
Haeckel, Ernst
512 Gutenberg downloadsen2016Difficulty 68 (Academic)
On Germinal Selection as a Source of Definite Variation
Weismann, August
512 Gutenberg downloadsen2010Difficulty 69 (Academic)
Physiology
Foster, M. (Michael), Sir
512 Gutenberg downloadsen2016Difficulty 39 (High School)
Studies of trees in winter : $b A description of the deciduous trees of northeastern America
Huntington, Annie Oakes
512 Gutenberg downloadsen2024Difficulty 51 (Graduate)
A Revision of Snakes of the Genus Conophis (Family Colubridae, from Middle America)
Wellman, John
511 Gutenberg downloadsen2011Difficulty 59 (Graduate)
The Biological Problem of To-day: Preformation Or Epigenesis? The Basis of a Theory of Organic Development
Hertwig, Oscar
511 Gutenberg downloadsen2011Difficulty 67 (Academic)
The Botanical Magazine, Vol. 08 Or, Flower-Garden Displayed
Curtis, William
511 Gutenberg downloadsen2008Difficulty 60 (Graduate)
Development of the Digestive Canal of the American Alligator
Reese, A. M. (Albert Moore)
510 Gutenberg downloadsen2007Difficulty 58 (Graduate)
The House Fly and How to Suppress It
Howard, L. O. (Leland Ossian) & Bishopp, F. C. (Fred Corry)
510 Gutenberg downloadsen2006Difficulty 54 (Graduate)
De Reis om de Wereld
Darwin, Charles
509 Gutenberg downloadsnl2010
Little Wanderers
Morley, Margaret Warner
509 Gutenberg downloadsen2020Difficulty 41 (College)
Marvels of Pond-life Or, A Year's Microscopic Recreations Among the Polyps, Infusoria, Rotifers, Water-bears and Polyzoa
Slack, Henry James
509 Gutenberg downloadsen2011Difficulty 74 (Expert)
Report on the Migration of Birds in the Spring and Autumn of 1881. Third Report
Harvie-Brown, J. A. (John Alexander) & Barrington, Richard Manliffe & Cordeaux, John & Kermode, P. M. C. (Philip Moore Callow) & More, Alexander Goodman
509 Gutenberg downloadsen2021Difficulty 41 (College)
Catholic Churchmen in Science [First Series] Sketches of the Lives of Catholic Ecclesiastics Who Were Among the Great Founders in Science
Walsh, James J. (James Joseph)
508 Gutenberg downloadsen2010Difficulty 67 (Academic)
A Description of the Bar-and-Frame-Hive With an Abstract of Wildman's Complete Guide for the Management of Bees Throughout the Year
Munn, William Augustus
507 Gutenberg downloadsen2006Difficulty 57 (Graduate)
Dans la Haute-Gambie : $b Voyage d'exploration scientifique, 1891-1892
Rançon, A. (André)
507 Gutenberg downloadsfr2024
Bee Keeping
Benton, Frank
506 Gutenberg downloadsen2015Difficulty 63 (Academic)
Science and Morals and Other Essays
Windle, Bertram Coghill Alan, Sir
506 Gutenberg downloadsen2008Difficulty 56 (Graduate)
De Wereld vóór de schepping van den mensch
Flammarion, Camille
505 Gutenberg downloadsnl2006
Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, IV. Band Das Emporblühen der modernen Naturwissenschaften seit der Entdeckung des Energieprinzips
Dannemann, Friedrich
505 Gutenberg downloadsde2019
Coral and Coral Reefs
Huxley, Thomas Henry
504 Gutenberg downloadsen2001Difficulty 58 (Graduate)
Lajien synty: Luonnollisen valinnan kautta
Darwin, Charles
503 Gutenberg downloadsfi2016
Palm trees of the Amazon and their uses
Wallace, Alfred Russel
503 Gutenberg downloadsen2023Difficulty 62 (Academic)
Daedalus : $b or, Science and the future
Haldane, J. B. S. (John Burdon Sanderson)
502 Gutenberg downloadsen2023Difficulty 58 (Graduate)
Some Common Birds in Their Relation to Agriculture
Beal, F. E. L. (Foster Ellenborough Lascelles)
502 Gutenberg downloadsen2020Difficulty 55 (Graduate)
Evolution
Watson, James A. S. (James Anderson Scott)
501 Gutenberg downloadsen2016Difficulty 60 (Graduate)
Les Phénomènes Psychiques Occultes: État Actuel de la Question
Coste, Albert
501 Gutenberg downloadsfr2013
Notes on Diseases of Swine, Sheep, Poultry and the Dog Cause, Symptoms and Treatments
Korinek, Charles James
501 Gutenberg downloadsen2019Difficulty 55 (Graduate)
A Taxonomic Study of the Middle American Snake, Pituophis deppei
Duellman, William Edward
500 Gutenberg downloadsen2010Difficulty 58 (Graduate)
Birds from Coahuila, Mexico
Urban, Emil K.
500 Gutenberg downloadsen2008Difficulty 55 (Graduate)
Poultry diseases Causes, symptoms and treatment, with notes on post-mortem examinations
Wortley, E. J. (E. Jocelyn)
500 Gutenberg downloadsen2022Difficulty 57 (Graduate)
The philosophy of biology
Johnstone, James
500 Gutenberg downloadsen2020Difficulty 65 (Academic)
Variation in the Muscles and Nerves of the Leg in Two Genera of Grouse (Tympanuchus and Pedioecetes)
Holmes, E. Bruce
500 Gutenberg downloadsen2013Difficulty 55 (Graduate)
The Diatomaceæ of Philadelphia and Vicinity
Boyer, Charles S. (Charles Sumner)
499 Gutenberg downloadsen2014Difficulty 67 (Academic)
The Fairy-Land of Science
Buckley, Arabella B. (Arabella Burton)
499 Gutenberg downloadsen2004Difficulty 48 (College)
Leprosy : $b in its clinical & pathological aspects
Hansen, G. Armauer (Gerhard Armauer) & Looft, Carl
498 Gutenberg downloadsen2023Difficulty 64 (Academic)
The modes of origin of lowest organisms including a discussion of the experiments of M. Pasteur
Bastian, H. Charlton
498 Gutenberg downloadsen2015Difficulty 71 (Expert)
The Perpetuation of Living Beings, Hereditary Transmission and Variation Lecture IV. (of VI.), "Lectures to Working Men", at the Museum of Practical Geology, 1863, on Darwin's Work: "Origin of Species"
Huxley, Thomas Henry
498 Gutenberg downloadsen2001Difficulty 66 (Academic)
Freshwater Sponges, Hydroids & Polyzoa
Annandale, Nelson
497 Gutenberg downloadsen2011Difficulty 61 (Academic)
Ecological Studies of the Timber Wolf in Northeastern Minnesota
Mech, L. David & Frenzel, Louis Daniel & Karns, P. D. & Ream, Robert R. & Winship, John W.
496 Gutenberg downloadsen2011Difficulty 52 (Graduate)
The Scientific Evidences of Organic Evolution
Romanes, George John
495 Gutenberg downloadsen2006Difficulty 67 (Academic)
Scientific American Supplement, No. 794, March 21, 1891
Various
494 Gutenberg downloadsen2005Difficulty 52 (Graduate)
The American Bee Journal, Volume VI, Number 3, September 1870
Various
494 Gutenberg downloadsen2018Difficulty 56 (Graduate)
The Forests of Mount Rainier National Park
Allen, G. F. (Grenville F.)
494 Gutenberg downloadsen2010Difficulty 49 (College)
Inheritance of Characteristics in Domestic Fowl
Davenport, Charles Benedict
493 Gutenberg downloadsen2015Difficulty 50 (College)
Scientific American Supplement, No. 286, June 25, 1881
Various
493 Gutenberg downloadsen2005Difficulty 53 (Graduate)
The Myxomycetes of the Miami Valley, Ohio
Morgan, A. P. (Andrew Price)
493 Gutenberg downloadsen2009Difficulty 64 (Academic)
A conchological manual
Sowerby, G. B. (George Brettingham)
492 Gutenberg downloadsen2013Difficulty 64 (Academic)
Food Poisoning
Jordan, Edwin O. (Edwin Oakes)
492 Gutenberg downloadsen2010Difficulty 65 (Academic)
Inorganic Plant Poisons and Stimulants
Brenchley, Winifred Elsie
492 Gutenberg downloadsen2015Difficulty 61 (Academic)
On the Preparations of the Indian Hemp, or Gunjah (Cannabis Indica) Their Effects on the Animal System in Health, and Their Utility in the Treatment of Tetanus and Other Convulsive Diseases
O'Shaughnessy, W. B.
492 Gutenberg downloadsen2022Difficulty 63 (Academic)
Pflanzenleben in Feld und Garten
Buckley, Arabella B. (Arabella Burton)
492 Gutenberg downloadsde2022
A Review of the Frogs of the Hyla bistincta Group
Duellman, William Edward
490 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Evolution and Classification of the Pocket Gophers of the Subfamily Geomyinae
Russell, Robert J.
488 Gutenberg downloadsen2012Difficulty 65 (Academic)
Stories of the Universe: Animal Life
Lindsay, B.
488 Gutenberg downloadsen2012Difficulty 51 (Graduate)
The Story of Creation as Told By Theology and By Science
Ackland, T. S. (Thomas Suter)
488 Gutenberg downloadsen2003Difficulty 62 (Academic)
The Birds of Australia, Vol. 5 of 7
Gould, John
487 Gutenberg downloadsen2020Difficulty 61 (Academic)
A Monograph of the Trilobites of North America: with Coloured Models of the Species
Green, Jacob
486 Gutenberg downloadsen2021Difficulty 63 (Academic)
Appletons' Popular Science Monthly, February 1899 Volume LIV, No. 4, February 1899
Various
486 Gutenberg downloadsen2013Difficulty 57 (Graduate)
The Evolution of Man — Volume 2
Haeckel, Ernst
486 Gutenberg downloadsen2004Difficulty 55 (Graduate)
The Present Method of Inoculating for the Small-Pox To which are added, some experiments, instituted with a view to discover the effects of a similar treatment in the natural small-pox
Dimsdale, Thomas
486 Gutenberg downloadsen2015Difficulty 68 (Academic)
The Evolution of Man — Volume 1
Haeckel, Ernst
485 Gutenberg downloadsen2004Difficulty 52 (Graduate)
Epidemic Respiratory Disease The pneumonias and other infections of the repiratory tract accompanying influenza and measles
Opie, Eugene L. (Eugene Lindsay) & Blake, Francis G. (Francis Gilman) & Rivers, Thomas M. (Thomas Milton) & Small, James C. (James Craig)
484 Gutenberg downloadsen2020Difficulty 67 (Academic)
Influenza : $b An epidemiologic study
Vaughan, Warren T. (Warren Taylor)
483 Gutenberg downloadsen2023Difficulty 66 (Academic)
Rapport sur une mission botanique exécutée en 1884 dans le nord, le sud et l'ouest de la Tunisie
Letourneux, A. (Aristide)
483 Gutenberg downloadsfr2024
Systematics of Megachiropteran Bats in the Solomon Islands
Phillips, Carleton J.
483 Gutenberg downloadsen2012Difficulty 58 (Graduate)
Little Busybodies: The Life of Crickets, Ants, Bees, Beetles, and Other Busybodies
Marks, Jeannette Augustus & Moody, Julia
482 Gutenberg downloadsen2007Difficulty 34 (High School)
Researches on the Visual Organs of the Trilobites
Lindström, Gustaf
482 Gutenberg downloadsen2022Difficulty 54 (Graduate)
The Botanical Magazine, Vol. 03 Or, Flower-Garden Displayed
Curtis, William
482 Gutenberg downloadsen2006Difficulty 57 (Graduate)
The Salmon Fishery of Penobscot Bay and River in 1895-96
Smith, Hugh M. (Hugh McCormick)
482 Gutenberg downloadsen2005Difficulty 48 (College)
A New Order of Fishlike Amphibia From the Pennsylvanian of Kansas
Eaton, Theodore H. (Theodore Hildreth) & Stewart, Peggy Lou
481 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Het Leven der Dieren: Deel 1, Hoofdstuk 04: De Roofdieren
Brehm, Alfred Edmund
481 Gutenberg downloadsnl2006
Note on the Resemblances and Differences in the Structure and the Development of the Brain in Man and Apes
Huxley, Thomas Henry & Darwin, Charles
481 Gutenberg downloadsen2000Difficulty 66 (Academic)
The Bedbug [1916]
Marlatt, C. L.
481 Gutenberg downloadsen2020Difficulty 61 (Academic)
The illustrated story of evolution
Gauvin, Marshall J. (Marshall Jerome)
481 Gutenberg downloadsen2023Difficulty 54 (Graduate)
Zoological Illustrations, Volume 2 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
480 Gutenberg downloadsen2012Difficulty 62 (Academic)
Ecological Observations on the Woodrat, Neotoma floridana
Fitch, Henry S. (Henry Sheldon) & Rainey, Dennis G.
479 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Pecan Diseases and Pests and Their Control
Rosburg, David W. & King, D. R.
479 Gutenberg downloadsen2021Difficulty 64 (Academic)
The apiary; or, bees, bee-hives, and bee culture [1866] Being a familiar account of the habits of bees, and the most improved methods of management, with full directions, adapted for the cottager, farmer, or scientific apiarian
Neighbor, Alfred
479 Gutenberg downloadsen2022Difficulty 59 (Graduate)
Comments on the Taxonomy and Geographic Distribution of Some North American Marsupials, Insectivores and Carnivores
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
478 Gutenberg downloadsen2010Difficulty 58 (Graduate)
Ohio Biological Survey, Bull. 10, Vol. 11, No. 6 The Ascomycetes of Ohio IV and V
Fink, Bruce & Hilker, Leafy Jane Corrington
478 Gutenberg downloadsen2006Difficulty 58 (Graduate)
Speciation of the Wandering Shrew
Findley, James S. (James Smith)
478 Gutenberg downloadsen2011Difficulty 62 (Academic)
Das Mikroskop und seine Anwendung Ein Leitfaden bei mikroskopischen Untersuchungen
Hager, Hermann
477 Gutenberg downloadsde2015
Het Leven der Dieren: Deel 1, Hoofdstuk 01: De Apen
Brehm, Alfred Edmund
476 Gutenberg downloadsnl2005
Speciation and Evolution of the Pygmy Mice, Genus Baiomys
Packard, Robert L. (Robert Lewis)
476 Gutenberg downloadsen2011Difficulty 64 (Academic)
The Natural History of Chocolate Being a Distinct and Particular Account of the Cocoa-Tree, its Growth and Culture, and the Preparation, Excellent Properties, and Medicinal Vertues of its Fruit
Quélus, D.
475 Gutenberg downloadsen2008Difficulty 52 (Graduate)
Improved Queen-Rearing; or, How to Rear Large, Prolific, Long-Lived Queen Bees The Result of Nearly Half a Century's Experience in Rearing Queen Bees, Giving the Practical, Every-day Work of the Queen-Rearing Apiary
Alley, Henry
474 Gutenberg downloadsen2019Difficulty 48 (College)
Het Leven der Dieren, Deel 3, Hoofdstuk 6: De Wormen
Brehm, Alfred Edmund
473 Gutenberg downloadsnl2020
The botanist's repository for new and rare plants; vol. 05 [of 10]
Andrews, Henry Cranke, active 1799-1828
473 Gutenberg downloadsen2024Difficulty 55 (Graduate)
A Profitable Instruction of the Perfite Ordering of Bees With the Maruellous Nature, Propertie, and Gouernemente of Them: and the Necessarie Vses Both of Their Honie and Waxe, Seruing Diuersly, as Well in Inward as Outward Causes: Gathered Out of the Best Writers
Hill, Thomas
472 Gutenberg downloadsen2014Difficulty 50 (College)
Aphorisms and Reflections from the Works of T. H. Huxley
Huxley, Thomas Henry
470 Gutenberg downloadsen2011Difficulty 60 (Graduate)
Journal of Entomology and Zoology, Vol. 11, No. 4, December 1919
Various
470 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Physiological economy in nutrition, with special reference to the minimal proteid requirement of the healthy man an experimental study
Chittenden, R. H. (Russell Henry)
470 Gutenberg downloadsen2022Difficulty 66 (Academic)
The Arena, Volume 18, No. 93, August, 1897
Various
470 Gutenberg downloadsen2010Difficulty 51 (Graduate)
Alpine flora of the Canadian Rocky Mountains
Brown, Stewardson
468 Gutenberg downloadsen2025Difficulty 60 (Graduate)
Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, III. Band Das Emporblühen der modernen Naturwissenschaften bis zur Entdeckung des Energieprinzipes
Dannemann, Friedrich
468 Gutenberg downloadsde2018
A Preliminary Revision of the North American Species of Cactus, Anhalonium, and Lophophora
Coulter, John Merle
466 Gutenberg downloadsen1998Difficulty 56 (Graduate)
Discourses: Biological & Geological Essays
Huxley, Thomas Henry
466 Gutenberg downloadsen2003Difficulty 61 (Academic)
Het Leven der Dieren, Deel 3, Hoofdstuk 5: De Spinachtigen
Brehm, Alfred Edmund
466 Gutenberg downloadsnl2020
The Destiny of Man, Viewed in the Light of His Origin
Fiske, John
466 Gutenberg downloadsen2005Difficulty 65 (Academic)
A Synopsis of the American Bats of the Genus Pipistrellus
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
465 Gutenberg downloadsen2010Difficulty 58 (Graduate)
Sir William Flower
Lydekker, Richard
465 Gutenberg downloadsen2025Difficulty 72 (Expert)
Von Sonnen und Sonnenstäubchen : $b Kosmische Wanderungen
Bölsche, Wilhelm
465 Gutenberg downloadsde2025
Het Leven der Dieren: Deel 1, Hoofdstuk 11: De Evenvingerigen
Brehm, Alfred Edmund
464 Gutenberg downloadsnl2007
La vie des termites
Maeterlinck, Maurice
464 Gutenberg downloadsfr2024
Les énigmes de l'Univers
Haeckel, Ernst
464 Gutenberg downloadsfr2012
New England Salmon Hatcheries and Salmon Fisheries in the Late 19th Century
Various
464 Gutenberg downloadsen2005Difficulty 53 (Graduate)
Q. E. D., or New Light on the Doctrine of Creation
Price, George McCready
464 Gutenberg downloadsen2004Difficulty 67 (Academic)
Scientific American Supplement, No. 664, September 22,1888
Various
464 Gutenberg downloadsen2008Difficulty 58 (Graduate)
Het Leven der Dieren: Deel 3.8, De Stekelhuidigen, Plantdieren en Sponsen
Brehm, Alfred Edmund
463 Gutenberg downloadsnl2020
Aus dem Leben der Insekten
Buckley, Arabella B. (Arabella Burton)
462 Gutenberg downloadsde2022
Degeneration: A Chapter in Darwinism
Lankester, E. Ray (Edwin Ray), Sir
462 Gutenberg downloadsen2019Difficulty 66 (Academic)
Jaw Musculature of the Mourning and White-winged Doves
Merz, Robert L.
462 Gutenberg downloadsen2010Difficulty 58 (Graduate)
Measles
Rucker, William Colby
462 Gutenberg downloadsen2006Difficulty 50 (College)
Some Common Birds Useful to the Farmer (1926 edition)
Beal, F. E. L. (Foster Ellenborough Lascelles)
462 Gutenberg downloadsen2020Difficulty 55 (Graduate)
An Expository Outline of the "Vestiges of the Natural History of Creation" With a Notice of the Author's "Explanations:" A Sequel to the Vestiges
Laing, S. (Samuel)
461 Gutenberg downloadsen2006Difficulty 66 (Academic)
The English moths and butterflies : $b Together with the plants, flowers, and fruits whereon they feed, and are usually found.
Wilkes, Benjamin
460 Gutenberg downloadsen2024Difficulty 58 (Graduate)
The Systematics of the Frogs of the Hyla Rubra Group in Middle America
León, Juan R.
460 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Descripción Geografica, Histórica y Estadística de Bolivia, Tomo 1.
Orbigny, Alcide Dessalines d'
459 Gutenberg downloadses2004
God and the World: A Survey of Thought
Robinson, Arthur William
459 Gutenberg downloadsen2009Difficulty 60 (Graduate)
Reis door Noord Amerika : $b Gedaan door den Heer Pieter Kalm
Kalm, Pehr
459 Gutenberg downloadsnl2023
Food Habits of the Thrushes of the United States
Beal, F. E. L. (Foster Ellenborough Lascelles)
457 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Natural History of the Prairie Vole (Mammalian Genus Microtus) [KU. Vol. 1 No. 7]
Jameson, E. W. (Everett Williams)
456 Gutenberg downloadsen2011Difficulty 52 (Graduate)
The Ohio naturalist, Vol. 1, No. 4, February 1901
Ohio State University. Biological Club
456 Gutenberg downloadsen2022Difficulty 49 (College)
Time and Life: Mr. Darwin's "Origin of Species"
Huxley, Thomas Henry
456 Gutenberg downloadsen2001Difficulty 72 (Expert)
Evolution: An Investigation and a Critique
Graebner, Theodore
454 Gutenberg downloadsen2006Difficulty 62 (Academic)
The Ohio naturalist, Vol. 1, No. 8, June 1901
Ohio State University. Biological Club
454 Gutenberg downloadsen2022Difficulty 51 (Graduate)
Darwin, and After Darwin, Volume 2 of 3 Post-Darwinian Questions: Heredity and Utility
Romanes, George John
453 Gutenberg downloadsen2011Difficulty 64 (Academic)
De martelaars der wetenschap
Tissandier, Gaston
453 Gutenberg downloadsnl2018
Über den Bildungstrieb
Blumenbach, Johann Friedrich
453 Gutenberg downloadsde2020
Common Diseases of Farm Animals
Craig, Robert Alexander
451 Gutenberg downloadsen2005Difficulty 55 (Graduate)
Emanuel Swedenborg's Investigations in Natural Science and the Basis for His Statements Concerning the Functions of the Brain
Ramström, Martin
451 Gutenberg downloadsen2020Difficulty 71 (Expert)
Fishes of Chautauqua, Cowley and Elk Counties, Kansas
Metcalf, Artie L.
451 Gutenberg downloadsen2010Difficulty 55 (Graduate)
The Dancing Mouse: A Study in Animal Behavior
Yerkes, Robert Mearns
451 Gutenberg downloadsen2005Difficulty 64 (Academic)
Fathers of Biology
McRae, Charles
450 Gutenberg downloadsen2008Difficulty 64 (Academic)
Memorias sobre a influencia dos descobrimentos portuguezes no conhecimento das plantas I. - Memoria sobre a Malagueta
Ficalho, Francisco Manuel de Melo, Conde de
450 Gutenberg downloadspt2009
Souvenirs entomologiques - Livre I Étude sur l'instinct et les moeurs des insectes
Fabre, Jean-Henri
450 Gutenberg downloadsfr2005
Studies of Birds Killed in Nocturnal Migration
Tordoff, Harrison Bruce & Mengel, Robert Morrow
450 Gutenberg downloadsen2016Difficulty 54 (Graduate)
The House We Live In; or, The Making of the Body
Farnsworth, Vesta J.
450 Gutenberg downloadsen2021Difficulty 31 (High School)
Unsere Haustiere vom Standpunkte ihrer wilden Verwandten
Zell, Th. (Theodor)
450 Gutenberg downloadsde2018
Catalogue of the dipterous insects collected at Singapore and Malacca
Wallace, Alfred Russel
449 Gutenberg downloadsen2023Difficulty 56 (Graduate)
De afstamming van den mensch Naar voordrachten in populair-wetenschappelijken vorm bewerkt
Boeke, Jan
449 Gutenberg downloadsnl2017
Mushroom and Toadstools How to Distinguish Easily the Differences Between Edible and Poisonous Fungi
Smith, Worthington George
449 Gutenberg downloadsen2019Difficulty 49 (College)
Aus den Tiefen des Weltmeeres Schilderungen von der deutschen Tiefsee-Expedition
Chun, Carl
448 Gutenberg downloadsde2014
La flore utile du bassin de la Gambie
Rançon, A. (André)
448 Gutenberg downloadsfr2024
Cholera and the Water Supply in the South Districts of London in 1854
Snow, John
447 Gutenberg downloadsen2021Difficulty 71 (Expert)
Het Leven der Dieren: Deel 3.7, De Weekdieren
Brehm, Alfred Edmund
447 Gutenberg downloadsnl2020
I funghi mangerecci e velenosi dell'Europa media con speciale riguardo a quelli che crescono nel Trentino - II edizione riveduta ed aumentata
Bresadola, Giacomo
447 Gutenberg downloadsit2013
The Botanical Magazine, Vol. 06 Or, Flower-Garden Displayed
Curtis, William
447 Gutenberg downloadsen2007Difficulty 60 (Graduate)
The botanist's repository for new and rare plants; vol. 07 [of 10]
Andrews, Henry Cranke, active 1799-1828
447 Gutenberg downloadsen2024Difficulty 57 (Graduate)
A synopsis of the palms of Puerto Rico
Cook, O. F. (Orator Fuller)
446 Gutenberg downloadsen2023Difficulty 63 (Academic)
Animal portraiture
Lydekker, Richard
446 Gutenberg downloadsen2023Difficulty 58 (Graduate)
Experimentelle Untersuchungen über die Frage »Ist die Furcht vor Krankheitsübertragung durch das Telephon berechtigt«? Inaugural-Dissertation zur Erlangung der Doktorwürde in der Medizin, Chirurgie und Geburtshülfe der Hohen Medizinischen Fakultät der Königlichen Universität Greifswald
Weiss, Carl
446 Gutenberg downloadsde2008
The Anatomy of Vegetables Begun With a General Account of Vegetation founded thereon
Grew, Nehemiah
446 Gutenberg downloadsen2018Difficulty 48 (College)
The giant sequoia : $b An account of the history and characteristics of the big trees of California
Ellsworth, Rodney Sydes
446 Gutenberg downloadsen2025Difficulty 56 (Graduate)
The history of a mouthful of bread : $b and its effect on the organization of men and animals
Macé, Jean
446 Gutenberg downloadsen2004Difficulty 49 (College)
A history of evolution
Fenton, Carroll Lane
445 Gutenberg downloadsen2025Difficulty 63 (Academic)
The Philosophy of Health; Volume 1 (of 2) or, an exposition of the physical and mental constitution of man
Smith, Southwood
444 Gutenberg downloadsen2019Difficulty 73 (Expert)
Meeresfische
Floericke, Kurt
443 Gutenberg downloadsde2018
Scientific Essays and Lectures
Kingsley, Charles
443 Gutenberg downloadsen2003Difficulty 56 (Graduate)
Histoire naturelle des oiseaux d'Afrique, t. 1
Le Vaillant, François
442 Gutenberg downloadsfr2018
The cretaceous birds of New Jersey
Olson, Storrs L. & Parris, David C.
442 Gutenberg downloadsen2022Difficulty 69 (Academic)
The zoology of the voyage of H.M.S. Beagle [vol. 2 of 5] : $b Mammalia
Waterhouse, G. R. (George Robert)
441 Gutenberg downloadsen2022Difficulty 53 (Graduate)
A Quantitative Study of the Nocturnal Migration of Birds
Lowery, George H., Jr.
440 Gutenberg downloadsen2011Difficulty 55 (Graduate)
An ethical problem; or, Sidelights upon scientific experimentation on man and animals
Leffingwell, Albert
440 Gutenberg downloadsen2006Difficulty 64 (Academic)
Journal of Entomology and Zoology, Vol. 11, No. 2, June 1919
Various
440 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Rapport sur une mission botanique exécutée en 1884 dans la région saharienne, au nord des grands chotts et dans les îles de la côte orientale de la Tunisie
Doumet-Adanson, Napoléon
440 Gutenberg downloadsfr2024
Zwischen Pol und Äquator: Tiergeographische Lebensbilder
Floericke, Kurt
440 Gutenberg downloadsde2022
Evolution of Life and Form Four lectures delivered at the twenty-third anniversary meeting of the Theosophical Society at Adyar, Madras, 1898
Besant, Annie
439 Gutenberg downloadsen2012Difficulty 60 (Graduate)
The Essentials of Illustration A Practical Guide to the Reproduction of Drawings & Photographs for the Use of Scientists & Others
Hill, Thomas George
439 Gutenberg downloadsen2011Difficulty 58 (Graduate)
The Pros and Cons of Vivisection
Richet, Charles
438 Gutenberg downloadsen2011Difficulty 63 (Academic)
A Field Study of the Kansas Ant-Eating Frog, Gastrophryne olivacea
Fitch, Henry S. (Henry Sheldon)
436 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Handboek voor den kaasmaker in Nederland
Hollman, Pierre Jean
436 Gutenberg downloadsnl2010
The Doctrine of Evolution: Its Basis and Its Scope
Crampton, Henry Edward
436 Gutenberg downloadsen2005Difficulty 65 (Academic)
An inaugural dissertation on pulmonary consumption
Delafield, Edward
434 Gutenberg downloadsen2022Difficulty 63 (Academic)
Carlo Darwin
Lessona, Michele
434 Gutenberg downloadsit2014
House Rats and Mice
Lantz, David E. (David Ernest)
434 Gutenberg downloadsen2011Difficulty 51 (Graduate)
Mammals Obtained by Dr. Curt von Wedel from the Barrier Beach of Tamaulipas, Mexico
Hall, E. Raymond (Eugene Raymond)
434 Gutenberg downloadsen2009Difficulty 53 (Graduate)
L'intelligence des fleurs
Maeterlinck, Maurice
433 Gutenberg downloadsfr2020
Het Leven der Dieren: Deel 3.9, De Oerdieren
Brehm, Alfred Edmund
432 Gutenberg downloadsnl2021
Louis Agassiz as a Teacher; illustrative extracts on his method of instruction
Cooper, Lane
432 Gutenberg downloadsen2004Difficulty 56 (Graduate)
On the phenomena of variation and geographical distribution as illustrated by the Papilionidæ of the Malayan region
Wallace, Alfred Russel
432 Gutenberg downloadsen2024Difficulty 66 (Academic)
Colour vision : $b Being the Tyndall Lectures delivered in 1894 at the Royal Institution
Abney, William de Wiveleslie, Sir
430 Gutenberg downloadsen2024Difficulty 55 (Graduate)
A Dissertation on Horses Wherein It is Demonstrated, by Matters of Fact, as Well as from the Principles of Philosophy, That Innate Qualities Do Not Exist, and That the Excellence of This Animal is Altogether Mechanical and Not in the Blood
Osmer, William
429 Gutenberg downloadsen2004Difficulty 64 (Academic)
In sloot en plas
Heimans, Eli & Thijsse, Jac. P. (Jacobus Pieter)
429 Gutenberg downloadsnl2022
The Forest Habitat of the University of Kansas Natural History Reservation
Fitch, Henry S. (Henry Sheldon) & McGregor, Ronald L.
429 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Säugethiere vom Celebes- und Philippinen-Archipel
Meyer, Adolf Bernhard
428 Gutenberg downloadsde2023
ABC's of Science
Oliver, Charles A. (Charles Alexander)
427 Gutenberg downloadsen1998Difficulty 51 (Graduate)
Antony van Leeuwenhoek, de ontdekker der infusorien, 1675-1875
Haaxman, P. J.
427 Gutenberg downloadsnl2021
Der Unterkiefer des Homo Heidelbergensis: Aus den Sanden von Mauer bei Heidelberg
Schoetensack, Otto
427 Gutenberg downloadsde2011
Le Tour du Monde; Voyage d'un naturaliste. Journal des voyages et des voyageurs; 2. sem. 1860
Various
427 Gutenberg downloadsfr2008
A Discourse on the Plague
Mead, Richard
426 Gutenberg downloadsen2010Difficulty 61 (Academic)
Marxism and Darwinism : $b Evidence, speeches, and papers in its favour
Pannekoek, Anton
426 Gutenberg downloadsen2023Difficulty 58 (Graduate)
Piebald rats and selection : $b An experimental test of the effectiveness of selection and of the theory of gametic purity in Mendelian crosses
Castle, William E. (William Ernest) & Phillips, John C. (John Charles)
426 Gutenberg downloadsen2024Difficulty 54 (Graduate)
Scientific American magazine, Vol. 2 Issue 1 The advocate of Industry and Journal of Scientific, Mechanical and Other Improvements
Various
426 Gutenberg downloadsen2009Difficulty 52 (Graduate)
Zakflora voor Suriname [Deel I] Bulletin van het Koloniaal Museum te Haarlem No. 47.
Pulle, A. A. (August Adriaan)
426 Gutenberg downloadsnl2017
Flytraps and Their Operation [1930]
Bishopp, F. C. (Fred Corry)
424 Gutenberg downloadsen2020Difficulty 51 (Graduate)
Phylogeny of the Waxwings and Allied Birds
Arvey, M. Dale (Martin Dale)
424 Gutenberg downloadsen2010Difficulty 66 (Academic)
Profitable poultry : $b Their management in health and disease
Tegetmeier, W. B. (William Bernhard)
424 Gutenberg downloadsen2024Difficulty 65 (Academic)
The Brain, A Decoded Enigma
Moisa, Dorin Teodor
424 Gutenberg downloadsen2005Difficulty 58 (Graduate)
The History of Esculent Fish
North, Roger
424 Gutenberg downloadsen2021Difficulty 47 (College)
Rapport sur un voyage botanique en Algérie, de Philippeville à Biskra et dans les Monts Aurès, entrepris en 1853 sous le patronage du Ministère de la guerre
Cosson, E. (Ernest)
423 Gutenberg downloadsfr2024
The botanist's repository for new and rare plants; vol. 08 [of 10]
Andrews, Henry Cranke, active 1799-1828
423 Gutenberg downloadsen2024Difficulty 58 (Graduate)
The Subspecific Status of Two Central American Sloths
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
423 Gutenberg downloadsen2010Difficulty 62 (Academic)
Coloured engravings of heaths; vol. 1
Andrews, Henry Cranke, active 1799-1828
422 Gutenberg downloadsen2023Difficulty 60 (Graduate)
Flowers and their friends
Morley, Margaret Warner
422 Gutenberg downloadsen2024Difficulty 39 (High School)
Le Sud-Oranais: études floristiques et phytogéographiques faites au cours d'une exploration dans le Sud-Ouest de l'Algérie en 1901
Hochreutiner, B. P. G. (Bénédict Pierre Georges)
422 Gutenberg downloadsfr2025
Report on the Migration of Birds in the Autumn of 1879. [First Report]
Harvie-Brown, J. A. (John Alexander) & Cordeaux, John
422 Gutenberg downloadsen2021Difficulty 40 (High School)
Systematic Status of the Colubrid Snake, Leptodeira discolor Günther
Duellman, William Edward
422 Gutenberg downloadsen2011Difficulty 63 (Academic)
Dairy Disagreeables Busy the Bacteriologists
Hall, Frank H. (Frank Henry) & Harding, Harry Alexis & Rogers, L. A. (Lore Alford) & Smith, George A.
421 Gutenberg downloadsen2022Difficulty 56 (Graduate)
The Genera of Phyllomedusine Frogs (Anura: Hylidae)
Duellman, William Edward
420 Gutenberg downloadsen2010Difficulty 74 (Expert)
Through a Microscope Something of the Science, Together with many Curious Observations Indoor and Out and Directions for a Home-made Microscope.
Wells, Samuel & Sargent, Frederick Leroy & Treat, Mary
420 Gutenberg downloadsen2011Difficulty 48 (College)
De Plantis Esculentis Insularum Oceani Australis Commentatio Botanica
Forster, Georg
419 Gutenberg downloadsla2011
Lamarck et son OEuvre
Corra, Emile
419 Gutenberg downloadsfr2012
A New Extinct Emydid Turtle from the Lower Pliocene of Oklahoma
Galbreath, Edwin C. (Edwin Carter)
418 Gutenberg downloadsen2010Difficulty 59 (Graduate)
A study of some factors influencing fertility and sterility in the bull
Gilman, Herbert Lester
418 Gutenberg downloadsen2024Difficulty 67 (Academic)
Archimedes; or, the future of physics
Whyte, Lancelot Law
418 Gutenberg downloadsen2025Difficulty 66 (Academic)
Earthworms and Their Allies
Beddard, Frank E. (Frank Evers)
418 Gutenberg downloadsen2013Difficulty 59 (Graduate)
Noteworthy Mammals from Sinaloa, Mexico
Jones, J. Knox & Alvarez, Ticul & Lee, M. Raymond
418 Gutenberg downloadsen2010Difficulty 52 (Graduate)
Aspects of Reproduction and Development in the Prairie Vole (Microtus ochrogaster)
Fitch, Henry S. (Henry Sheldon)
416 Gutenberg downloadsen2011Difficulty 60 (Graduate)
Myology and Serology of the Avian Family Fringillidae: A Taxonomic Study
Stallcup, William B.
416 Gutenberg downloadsen2010Difficulty 65 (Academic)
Sweet-Clover Seed
Coe, H. S. & Martin, John N. (John Nathan)
416 Gutenberg downloadsen2020Difficulty 60 (Graduate)
A Theory of Creation: A Review of 'Vestiges of the Natural History of Creation'
Bowen, Francis
415 Gutenberg downloadsen2008Difficulty 67 (Academic)
The Ancestry of Modern Amphibia: A Review of the Evidence
Eaton, Theodore H. (Theodore Hildreth)
415 Gutenberg downloadsen2011Difficulty 69 (Academic)
The Breeding Birds of Kansas
Johnston, Richard F.
415 Gutenberg downloadsen2011Difficulty 74 (Expert)
Vivisection
Leffingwell, Albert
415 Gutenberg downloadsen2010Difficulty 64 (Academic)
Embryology: The Beginnings of Life
Leighton, Gerald R. (Gerald Rowley)
414 Gutenberg downloadsen2011Difficulty 59 (Graduate)
Preservation of Bull Semen at Sub-Zero Temperatures
VanDemark, N. L. & Friedman, M. E. & Kinney, W. C. & Miller, W. J. & Rodriguez, Carlos
414 Gutenberg downloadsen2011Difficulty 62 (Academic)
Proceedings of the California Academy of Sciences, Series 3, Volume 4 (Zoology)
Various
414 Gutenberg downloadsen2017Difficulty 70 (Academic)
Saunders' Books on Pathology, Physiology Histology, Embryology and Bacteriology
W.B. Saunders Company
414 Gutenberg downloadsen2017Difficulty 61 (Academic)
The Hunterian lectures on colour-vision and colour-blindness
Edridge-Green, F. W. (Frederick William)
414 Gutenberg downloadsen2025Difficulty 56 (Graduate)
A bacteriological study of ham souring
McBryde, Charles Neil
413 Gutenberg downloadsen2022Difficulty 59 (Graduate)
Systematic Status of a South American Frog, Allophryne ruthveni Gaige
Lynch, John D. & Freeman, Howard L.
413 Gutenberg downloadsen2010Difficulty 63 (Academic)
Occurrence of the Garter Snake, Thamnophis sirtalis, in the Great Plains and Rocky Mountains
Fitch, Henry S. (Henry Sheldon) & Maslin, T. Paul
412 Gutenberg downloadsen2010Difficulty 66 (Academic)
Popular Lectures on Zoonomia Or The Laws of Animal Life, in Health and Disease
Garnett, Thomas
412 Gutenberg downloadsen2009Difficulty 59 (Graduate)
The Darwinian Hypothesis
Huxley, Thomas Henry
412 Gutenberg downloadsen2001Difficulty 69 (Academic)
The Subspecies of the Mountain Chickadee
Grinnell, Joseph
411 Gutenberg downloadsen2010Difficulty 50 (College)
A Population Study of the Prairie Vole (Microtus ochrogaster) in Northeastern Kansas
Martin, Edwin Perry
410 Gutenberg downloadsen2012Difficulty 61 (Academic)
A Statement of Facts Tending to Establish an Estimate of the True Value and Present State of Vaccination
Blane, Gilbert, Sir
410 Gutenberg downloadsen2022Difficulty 67 (Academic)
Biology : $b A lecture delivered at Columbia University in the series on Science, Philosophy and Art November 20, 1907
Wilson, Edmund B. (Edmund Beecher)
410 Gutenberg downloadsen2006Difficulty 69 (Academic)
Insect manufactures
Anonymous
410 Gutenberg downloadsen2024Difficulty 60 (Graduate)
A New Subspecies of Lizard, Cnemidophorus sacki, from Michoacán, México
Duellman, William Edward
409 Gutenberg downloadsen2010Difficulty 58 (Graduate)
Birds Found on the Arctic Slope of Northern Alaska
Bee, James W.
409 Gutenberg downloadsen2010Difficulty 42 (College)
Coloured engravings of heaths; vol. 3
Andrews, Henry Cranke, active 1799-1828
409 Gutenberg downloadsen2023Difficulty 66 (Academic)
Descriptions of New Hylid Frogs From Mexico and Central America
Duellman, William Edward
409 Gutenberg downloadsen2010Difficulty 64 (Academic)
The Botanical Magazine, Vol. 13 Or, Flower-Garden Displayed
Curtis, William & Sims, John
409 Gutenberg downloadsen2013Difficulty 58 (Graduate)
Woher die Kindlein kommen
Hoppeler, Hans
408 Gutenberg downloadsde2009
Im Zauber des Tierlebens
Lucanus, Friedrich von
407 Gutenberg downloadsde2024
Nouvel atlas de poche des champignons Comestibles et Vénéneux les plus répandus. Série I (Troisième édition) Suivi de notions générales sur les champignons, leur classification, composition chimique, valeur alimentaire, préparation
Dumée, Paul
407 Gutenberg downloadsfr2010
Handboek voor Bijenhouders
Dirks, J.
406 Gutenberg downloadsnl2010
Het Leven der Dieren: Deel 1, Hoofdstuk 07: De Knaagdieren
Brehm, Alfred Edmund
406 Gutenberg downloadsnl2007
The British Woodlice Being a Monograph of the Terrestrial Isopod Crustacea Occurring in the British Islands
Webb, Wilfred Mark & Sillem, Charles
406 Gutenberg downloadsen2013Difficulty 58 (Graduate)
Het Leven der Dieren: Deel 2, Hoofdstuk 01: De Boomvogels.
Brehm, Alfred Edmund
405 Gutenberg downloadsnl2009
Kyphosis and other Variations in Soft-shelled Turtles
Smith, Hobart M. (Hobart Muir)
404 Gutenberg downloadsen2010Difficulty 46 (College)
Muistelmia hyönteismaailmasta: Kuvauksia hyönteisten tavoista ja vaistosta
Fabre, Jean-Henri
404 Gutenberg downloadsfi2021
Beginselen der dierkunde
Ritzema Bos, J. (Jan)
403 Gutenberg downloadsnl2010
Cranial Osteology of the Hylid Frog, Smilisca baudini
Trueb, Linda
403 Gutenberg downloadsen2010Difficulty 61 (Academic)
Les grands froids
Bouant, Emile
403 Gutenberg downloadsfr2013
Darwinism. The Noachian Flood A lecture delivered before the Torquay Natural History Society, Jan. 31st, 1870
Stebbing, Thomas Roscoe Rede
402 Gutenberg downloadsen2021Difficulty 68 (Academic)
Subspeciation in Pocket Gophers of Kansas, [KU. Vol. 1 No. 11]
Villa Ramírez, Bernardo & Hall, E. Raymond (Eugene Raymond)
400 Gutenberg downloadsen2011Difficulty 58 (Graduate)
Geographic Variation in the North American Cyprinid Fish, Hybopsis gracilis
Olund, Leonard J. & Cross, Frank B. (Frank Bernard)
399 Gutenberg downloadsen2011Difficulty 57 (Graduate)
The bedbug : $b Its relation to public health, its habits and life history, and methods of control
United States. Public Health Service
399 Gutenberg downloadsen2023Difficulty 60 (Graduate)
The heathery; or, A monograph of the genus Erica. vol. 1
Andrews, Henry Cranke, active 1799-1828
399 Gutenberg downloadsen2022Difficulty 52 (Graduate)
The heathery; or, A monograph of the genus Erica. vol. 3
Andrews, Henry Cranke, active 1799-1828
399 Gutenberg downloadsen2023Difficulty 56 (Graduate)
Fishes of the Big Blue River Basin, Kansas
Minckley, W. L.
398 Gutenberg downloadsen2011Difficulty 47 (College)
Two New Meadow Mice from Michoacán Mexico
Hall, E. Raymond (Eugene Raymond)
398 Gutenberg downloadsen2010Difficulty 60 (Graduate)
A természettudomány fejlődésének története (1. kötet)
Bölsche, Wilhelm
397 Gutenberg downloadshu2022
Fish Populations, Following a Drought, in the Neosho and Marais des Cygnes Rivers of Kansas
Deacon, James E.
397 Gutenberg downloadsen2010Difficulty 52 (Graduate)
Hormones and Heredity A Discussion of the Evolution of Adaptations and the Evolution of Species
Cunningham, J. T. (Joseph Thomas)
397 Gutenberg downloadsen2005Difficulty 73 (Expert)
Texas Honey Plants
Sanborn, Charles Emerson & Scholl, Ernest E. (Ernest Emmett)
396 Gutenberg downloadsen2012Difficulty 53 (Graduate)
The Speech of Monkeys
Garner, R. L. (Richard Lynch)
396 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Uit de dierenwereld van het water Schetsen in woord en beeld van het lever der lagere diersoorten
Snijders, A. J. C. (Anthony J. C.)
396 Gutenberg downloadsnl2022
International Weekly Miscellany of Literature, Art and Science — Volume 1, No. 2, July 8, 1850
Various
395 Gutenberg downloadsen2004Difficulty 59 (Graduate)
Type specimens of amphibians and reptiles in the Museum of Natural History, the University of Kansas
Duellman, William Edward & Berg, Barbara
395 Gutenberg downloadsen2024Difficulty 56 (Graduate)
De la télépathie: Étude sur la transmission de la pensée
Hureau, Émile
394 Gutenberg downloadsfr2006
The puzzle of life and how it has been put together : $b A short history of the formation of the earth, with its vegetable and animal life, from the earliest times, including an account of prehistoric man, his weapons, tools, and works
Nicols, Arthur
394 Gutenberg downloadsen2025Difficulty 49 (College)
Zoological Illustrations, Volume 3 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
394 Gutenberg downloadsen2012Difficulty 60 (Graduate)
Le piante utili dell' Eritrea
Schweinfurth, Georg August
393 Gutenberg downloadsit2025
Ilex cassine, the aboriginal North American tea $b Its history, distribution, and use among the native North American Indians
Hale, Edwin M. (Edwin Moses)
392 Gutenberg downloadsen2023Difficulty 52 (Graduate)
Two New Pocket Gophers from Wyoming and Colorado
Hall, E. Raymond (Eugene Raymond) & Montague, H. Gordon
392 Gutenberg downloadsen2009Difficulty 51 (Graduate)
Biological analogies in history
Roosevelt, Theodore
391 Gutenberg downloadsen2023Difficulty 70 (Academic)
Comments on the Taxonomy and Geographic Distribution of Some North American Rodents
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
391 Gutenberg downloadsen2010Difficulty 56 (Graduate)
The Body at Work: A Treatise on the Principles of Physiology
Hill, Alex
391 Gutenberg downloadsen2020Difficulty 54 (Graduate)
The Pocket Gophers (Genus Thomomys) of Utah University of Kansas Publications, Museum of Natural History, Vol. 1 No. 1
Durrant, Stephen David
391 Gutenberg downloadsen2012Difficulty 57 (Graduate)
A Bilateral Division of the Parietal Bone in a Chimpanzee; with a Special Reference to the Oblique Sutures in the Parietal
Hrdlička, Aleš
390 Gutenberg downloadsen2010Difficulty 65 (Academic)
A Mechanico-Physiological Theory of Organic Evolution
Nägeli, Carl
390 Gutenberg downloadsen2010Difficulty 74 (Expert)
An Annotated Check List of the Mammals of Michoacán, México
Hall, E. Raymond (Eugene Raymond) & Villa Ramírez, Bernardo
390 Gutenberg downloadsen2012Difficulty 55 (Graduate)
Het Leven der Dieren: Deel 1, Hoofdstuk 08: De Tandeloozen; Hoofdstuk 09: De Slurfdieren; Hoofdstuk 10: De Onevenvingerigen
Brehm, Alfred Edmund
390 Gutenberg downloadsnl2007
Illustrations of the birds of Jamaica
Gosse, Philip Henry
390 Gutenberg downloadsen2024Difficulty 48 (College)
The Vitamine Manual
Eddy, Walter Hollis
390 Gutenberg downloadsen2005Difficulty 58 (Graduate)
Bedenkingen tegen de Leer van Darwin Gevolgd door beschouwingen over eenige philosophische onderwerpen.
Reuther, Antoine Charles
389 Gutenberg downloadsnl2009
Die organische Chemie in ihrer Anwendung auf Physiologie und Pathologie
Liebig, Justus, Freiherr von
389 Gutenberg downloadsde2017
Genera and Subgenera of Chipmunks
White, John A.
389 Gutenberg downloadsen2009Difficulty 61 (Academic)
Illustrated Index of British Shells Containing figures of all the recent species
Sowerby, G. B. (George Brettingham)
389 Gutenberg downloadsen2013Difficulty 53 (Graduate)
Observations on the Mississippi Kite in Southwestern Kansas
Fitch, Henry S. (Henry Sheldon)
389 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Sertum Anglicum, seu, Plantae Rariores quae in Hortis Juxta Londinum Imprimis in Horto Regio Kewensi excoluntur, ab anno 1786 ad annum 1787 observata
L'Héritier de Brutelle, Charles Louis
389 Gutenberg downloadsla2012
Zoological Illustrations, Second Series, Volume 3 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
389 Gutenberg downloadsen2013Difficulty 61 (Academic)
Études sur la flore du Sénégal
Vallot, Joseph
389 Gutenberg downloadsfr2024
Das Protistenreich : $b eine populäre Uebersicht über das Formengebiet der niedersten Lebewesen; Mit einem wissenschaftlichen Anhange: System der Protisten
Haeckel, Ernst
388 Gutenberg downloadsde2025
The Bedbug [1934]
Marlatt, C. L.
388 Gutenberg downloadsen2020Difficulty 62 (Academic)
Coloured engravings of heaths; vol. 4
Andrews, Henry Cranke, active 1799-1828
387 Gutenberg downloadsen2023Difficulty 60 (Graduate)
Comments on the Taxonomy and Geographic Distribution of North American Microtines
Hall, E. Raymond (Eugene Raymond) & Cockrum, E. Lendell
386 Gutenberg downloadsen2009Difficulty 62 (Academic)
Geschichte der Zoologie
Burckhardt, Rudolf
386 Gutenberg downloadsde2024
Some possible bearings of genetics on pathology
Morgan, Thomas Hunt
386 Gutenberg downloadsen2023Difficulty 57 (Graduate)
A New Subspecies of Slider Turtle (Pseudemys scripta) from Coahuila, México
Legler, John M.
385 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Flytraps and Their Operation [1921]
Bishopp, F. C. (Fred Corry)
385 Gutenberg downloadsen2020Difficulty 48 (College)
Gorillas & Chimpanzees
Garner, R. L. (Richard Lynch)
385 Gutenberg downloadsen2013Difficulty 51 (Graduate)
Den Waaragtigen Omloop des Bloeds
Leeuwenhoek, Antoni van
384 Gutenberg downloadsnl2006
Het Leven der Dieren: Deel 2, Hoofdstuk 02: De Papegaaien; Hoofdstuk 03: De Duifvogels
Brehm, Alfred Edmund
384 Gutenberg downloadsnl2009
Notizie del pubblico giardino de' semplici di Padova compilate intorno l'anno 1771
Marsili, Giovanni
384 Gutenberg downloadsit2005
Pleistocene Bats from San Josecito Cave, Nuevo Leon, Mexico
Jones, J. Knox
384 Gutenberg downloadsen2009Difficulty 55 (Graduate)
Mammals of the San Gabriel Mountains of California
Vaughan, Terry A.
383 Gutenberg downloadsen2011Difficulty 63 (Academic)
Phrenological Development of Robert Burns From a Cast of His Skull Moulded at Dumfries, the 31st Day of March 1834
Combe, George
383 Gutenberg downloadsen2009Difficulty 58 (Graduate)
The Baculum in Microtine Rodents
Anderson, Sydney
383 Gutenberg downloadsen2011Difficulty 64 (Academic)
The Italian Alp-bee; or, The gold mine of husbandry short and practical instructions to breed genuine prolific Italian queens; to multiply them by hundreds in a few months and how to change German hives into Italian
Hermann, H. C. (Heinrich C.)
383 Gutenberg downloadsen2023Difficulty 51 (Graduate)
An Annotated Checklist of Nebraskan Bats
Webb, Olin L. & Jones, J. Knox
382 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Records of the Fossil Mammal Sinclairella, Family Apatemyidae, From the Chadronian and Orellan
Clemens, William A. (William Alvin)
380 Gutenberg downloadsen2009Difficulty 57 (Graduate)
Seventeen Species of Bats Recorded from Barro Colorado Island, Panama Canal Zone
Hall, E. Raymond (Eugene Raymond) & Jackson, William B.
378 Gutenberg downloadsen2009Difficulty 49 (College)
A New Genus of Pennsylvanian Fish (Crossopterygii, Coelacanthiformes) from Kansas
Echols, Joan
377 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Description of a New Softshell Turtle from the Southeastern United States
Webb, Robert G. (Robert Gravem)
377 Gutenberg downloadsen2010Difficulty 60 (Graduate)
The Ohio Naturalist, Vol. II, No. 1, November, 1901
Ohio State University. Biological Club
377 Gutenberg downloadsen2023Difficulty 53 (Graduate)
Fruits of the Hawaiian Islands
Wilder, Gerrit Parmile
376 Gutenberg downloadsen2013Difficulty 52 (Graduate)
The Gospel of Evolution From "The Atheistic Platform", Twelve Lectures
Aveling, Edward B.
375 Gutenberg downloadsen2011Difficulty 55 (Graduate)
The heathery; or, A monograph of the genus Erica. vol. 2
Andrews, Henry Cranke, active 1799-1828
375 Gutenberg downloadsen2023Difficulty 54 (Graduate)
All about Ferrets and Rats A Complete History of Ferrets, Rats, and Rat Extermination from Personal Experiences and Study. Also a Practical Hand-Book on the Ferret.
Isaacsen, Adolph
374 Gutenberg downloadsen2013Difficulty 48 (College)
Höherzüchtung des Menschen auf biologischer Grundlage. Vortrag
Franze, Paul Christian
374 Gutenberg downloadsde2013
Which Shall Live—Men or Animals?
Baynes, Ernest Harold
373 Gutenberg downloadsen2021Difficulty 61 (Academic)
Zeugnisse für die Stellung des Menschen in der Natur
Huxley, Thomas Henry
373 Gutenberg downloadsde2010
Geographic Range of the Hooded Skunk, Mephitis macroura With Description of a New Subspecies from Mexico
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
372 Gutenberg downloadsen2010Difficulty 57 (Graduate)
Het Leven der Dieren: Deel 1, Hoofdstuk 12: Sirenen; Hoofdstuk 13: Walvischachtigen
Brehm, Alfred Edmund
371 Gutenberg downloadsnl2007
Additions to the List of the Birds of Louisiana
Lowery, George H., Jr.
370 Gutenberg downloadsen2010Difficulty 61 (Academic)
Comments on the Taxonomy and Geographic Distribution of Some North American Rabbits
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
370 Gutenberg downloadsen2009Difficulty 58 (Graduate)
Descriptions of Two Species of Frogs, Genus Ptychohyla Studies of American Hylid Frogs, V
Duellman, William Edward
370 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Methods of Destroying Rats
Lantz, David E. (David Ernest)
370 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Scientific American Supplement, No. 648, June 2, 1888.
Various
370 Gutenberg downloadsen2011Difficulty 54 (Graduate)
A Statistical Inquiry Into the Nature and Treatment of Epilepsy
Bennett, Alexander Hughes
369 Gutenberg downloadsen2011Difficulty 44 (College)
Species Plantarum, Sections XI-XIII
Linné, Carl von
369 Gutenberg downloadsla2010
The heathery; or, A monograph of the genus Erica. vol. 4
Andrews, Henry Cranke, active 1799-1828
369 Gutenberg downloadsen2023Difficulty 56 (Graduate)
Home Range and Movements of the Eastern Cottontail in Kansas
Janes, Donald W.
368 Gutenberg downloadsen2009Difficulty 55 (Graduate)
La philosophie zoologique avant Darwin
Perrier, Edmond
368 Gutenberg downloadsfr2010
Mammals taken Along the Alaska Highway
Baker, Rollin H. (Rollin Harold)
368 Gutenberg downloadsen2010Difficulty 47 (College)
Meinauer Naturlehre
Unknown
368 Gutenberg downloadsde2009
Palæontological Report of the Princeton Scientific Expedition of 1877
Osborn, Henry Fairfield & Scott, William Berryman & Speir, Francis
368 Gutenberg downloadsen2021Difficulty 56 (Graduate)
The Domestic Cat
Stables, Gordon
368 Gutenberg downloadsen2011Difficulty 51 (Graduate)
Morphological Variation in a Population of the Snake, Tantilla gracilis Baird and Girard
Hardy, Laurence M. & Cole, Charles J.
367 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Taxonomic Notes on Mexican Bats of the Genus Rhogeëssa
Hall, E. Raymond (Eugene Raymond)
367 Gutenberg downloadsen2010Difficulty 50 (College)
Aus Natur und Geisteswelt Sammlung wissenschaftlich-gemeinverständlicher Darstellungen aus allen Gebieten des Wissens
B.G. Teubner (Firm)
366 Gutenberg downloadsde2016
Darwin, and After Darwin, Volume 3 of 3 Post-Darwinian Questions: Isolation and Physiological Selection
Romanes, George John
366 Gutenberg downloadsen2011Difficulty 66 (Academic)
Einheimische Fische; Die Süßwasserfische unsrer Heimat
Floericke, Kurt
366 Gutenberg downloadsde2012
Mushrooms of America, Edible and Poisonous
Unknown
366 Gutenberg downloadsen2009Difficulty 49 (College)
The heathery; or, A monograph of the genus Erica. vol. 6
Andrews, Henry Cranke, active 1799-1828
366 Gutenberg downloadsen2023Difficulty 58 (Graduate)
Birds and Nature Vol. 09 No. 3 [March 1901]
Various
365 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Prodromus Florae Norfolkicae Sive, Catalogus stirpium quae in insula Norfolk annis 1804 et 1805 a Ferdinando Bauer collectae et depictae, nunc in Museo caesareo palatino rerum naturalium Vindobonae servantur
Endlicher, Stephan
365 Gutenberg downloadsla2012
The Behavior of the Honey Bee in Pollen Collecting
Casteel, Dana Brackenridge
365 Gutenberg downloadsen2012Difficulty 54 (Graduate)
The little book of British quadrupeds
May, W.
365 Gutenberg downloadsen2024Difficulty 44 (College)
Determining the Age of Cattle by the Teeth
Pope, George W. (George Whitfield)
364 Gutenberg downloadsen2008Difficulty 52 (Graduate)
Natural History of the Brush Mouse (Peromyscus boylii) in Kansas With Description of a New Subspecies
Long, Charles Alan
364 Gutenberg downloadsen2010Difficulty 51 (Graduate)
Plague Its Cause and the Manner of its Extension, Its Menace, Its Control and Suppression, Its Diagnosis and Treatment
Jackson, Thomas Wright
364 Gutenberg downloadsen2013Difficulty 68 (Academic)
Five Natural Hybrid Combinations in Minnows (Cyprinidae)
Cross, Frank B. (Frank Bernard) & Minckley, W. L.
363 Gutenberg downloadsen2011Difficulty 55 (Graduate)
A New Subspecies of the Black Myotis (Bat) from Eastern Mexico
Hall, E. Raymond (Eugene Raymond) & Alvarez, Ticul
362 Gutenberg downloadsen2008Difficulty 55 (Graduate)
Observations on the Terataspis grandis, Hall, the largest known trilobite
Clarke, John Mason
361 Gutenberg downloadsen2022Difficulty 60 (Graduate)
The chocolate-plant (Theobroma cacao) and its products
Anonymous
360 Gutenberg downloadsen2025Difficulty 55 (Graduate)
Bacteria in Daily Life
Frankland, Grace C.
359 Gutenberg downloadsen2013Difficulty 81 (Specialist)
Die Zelle
Kahn, Fritz
359 Gutenberg downloadsde2012
A Taxonomic Revision of the Leptodactylid Frog Genus Syrrhophus Cope
Lynch, John D.
358 Gutenberg downloadsen2011Difficulty 64 (Academic)
Careers in Atomic Energy
McIlhenny, Loyce J.
358 Gutenberg downloadsen2013Difficulty 68 (Academic)
Het Leven der Dieren: Hoofdstuk 7: De Pluviervogels
Brehm, Alfred Edmund
358 Gutenberg downloadsnl2010
A New Bog Lemming (Genus Synaptomys) From Nebraska
Jones, J. Knox
357 Gutenberg downloadsen2010Difficulty 62 (Academic)
The Microscope
Ross, Andrew
357 Gutenberg downloadsen2013Difficulty 65 (Academic)
Thoracic and Coracoid Arteries In Two Families of Birds, Columbidae and Hirundinidae
Jenkinson, Marion Anne
357 Gutenberg downloadsen2010Difficulty 64 (Academic)
A New Name for the Mexican Red Bat
Hall, E. Raymond (Eugene Raymond)
356 Gutenberg downloadsen2007Difficulty 55 (Graduate)
Breves instrucções aos correspondentes da Academia das Sciencias de Lisboa sobre as remessas dos productos, e noticias pertencentes a' Historia da Natureza, para formar hum Museo Nacional
Unknown
356 Gutenberg downloadspt2005
A New Bat (Myotis) From Mexico
Hall, E. Raymond (Eugene Raymond)
355 Gutenberg downloadsen2010Difficulty 57 (Graduate)
Comments on the Taxonomic Status of Apodemus peninsulae, with Description of a New Subspecies from North China
Jones, J. Knox
355 Gutenberg downloadsen2010Difficulty 62 (Academic)
Das Protoplasma der Rhizopoden und der Pflanzenzellen ein Beitrag zur Theorie der Zelle
Schultze, Max
355 Gutenberg downloadsde2022
Het Leven der Dieren: Deel 1, Hoofdstuk 02: De Halfapen; Hoofdstuk 03: De Vleermuizen
Brehm, Alfred Edmund
355 Gutenberg downloadsnl2005
Hints on the History and Management of the Honey Bee Being the Substance of Two Lectures Read Before the Members of the Hereford Literary, Philosophical, and Antiquarian Institution, in the Winter of 1850-51
Bevan, Edward
355 Gutenberg downloadsen2022Difficulty 64 (Academic)
On the Variation of Species, with Especial Reference to the Insecta Followed by an Inquiry into the Nature of Genera
Wollaston, Thomas Vernon
355 Gutenberg downloadsen2012Difficulty 78 (Expert)
Vasárnapi Könyv. 1914. Első félév 15. füzet
Various
355 Gutenberg downloadshu2009
Der Mensch der Zukunft
Bölsche, Wilhelm
354 Gutenberg downloadsde2018
The Subspecies of the Mexican Red-Bellied Squirrel, Sciurus aureogaster
Kelson, Keith R.
354 Gutenberg downloadsen2010Difficulty 61 (Academic)
Het Leven der Dieren: Deel 2, Hoofdstuk 05: De Ralvogels; Hoofdstuk 06: De Kraanvogels
Brehm, Alfred Edmund
353 Gutenberg downloadsnl2009
Sciências Naturaes Pela Redacção da «Educação Nacional»
Anonymous
352 Gutenberg downloadspt2006
De honig en zijn gebruik
Rondou, W.-F.
351 Gutenberg downloadsnl2008
Pliocene and Pleistocene Records of Fossil Turtles from Western Kansas and Oklahoma University of Kansas Publications Museum of Natural History Volume 1
Galbreath, Edwin C. (Edwin Carter)
351 Gutenberg downloadsen2010Difficulty 60 (Graduate)
The Meaning of Infancy
Fiske, John
351 Gutenberg downloadsen2004Difficulty 62 (Academic)
Het Leven der Dieren: Deel 1, Hoofdstuk 14: Buideldieren; Hoofdstuk 15: Kloakdieren
Brehm, Alfred Edmund
350 Gutenberg downloadsnl2007
Nests and Eggs of Familiar British Birds, Second Series Described and Illustrated; with an Account of the Haunts and Habits of the Feathered Architects, and their Times and Modes of Building
Adams, H. G. (Henry Gardiner)
350 Gutenberg downloadsen2012Difficulty 60 (Graduate)
Notes on Veterinary Anatomy
Korinek, Charles James
350 Gutenberg downloadsen2019Difficulty 53 (Graduate)
The American Bee Journal, Vol. VI., Number 5, November 1870
Various
350 Gutenberg downloadsen2018Difficulty 53 (Graduate)
Coyotes in Their Economic Relations
Lantz, David E. (David Ernest)
349 Gutenberg downloadsen2014Difficulty 54 (Graduate)
The suppression of tuberculosis $b Together with observations concerning phthisiogenesis in man and animals and suggestions concerning the hygiene of cow stables and the production of milk for infant-feeding, with special reference to tuberculosis
Behring, Emil von
349 Gutenberg downloadsen2023Difficulty 67 (Academic)
Der Tabak: Studien über seine Kultur und Biologie
Koning, C. J. (Cornelis Johan)
348 Gutenberg downloadsde2016
The Ornithosauria An elementary study of the bones of Pterodactyles made from fossil remains found in the Cambridge Upper Greensand, and arranged in the Woodwardian Museum of the University of Cambridge
Seeley, H. G. (Harry Govier)
348 Gutenberg downloadsen2016Difficulty 58 (Graduate)
Descriptive Zoopraxography; or, the science of animal locomotion made popular
Muybridge, Eadweard
347 Gutenberg downloadsen2012Difficulty 72 (Expert)
A New Subspecies of Microtus montanus from Montana and Comments on Microtus canicaudus Miller
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
346 Gutenberg downloadsen2009Difficulty 58 (Graduate)
Cruise of the Revenue-Steamer Corwin in Alaska and the N.W. Arctic Ocean in 1881: Botanical Notes Notes and Memoranda: Medical and Anthropological; Botanical; Ornithological.
Muir, John
346 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Het Leven der Dieren: Deel 1, Hoofdstuk 05: Robben; Hoofdstuk 06: Insecteneters
Brehm, Alfred Edmund
346 Gutenberg downloadsnl2006
Journal of Entomology and Zoology, Vol. 11, No. 1, March 1919
Various
346 Gutenberg downloadsen2014Difficulty 62 (Academic)
Adequate Preparation for the Teacher of Biological Sciences in Secondary Schools
McDonald, J. Daley (James Daley)
345 Gutenberg downloadsen2010Difficulty 64 (Academic)
Notes on Philippine Birds Collected by Governor W. Cameron Forbes Bulletin of the Museum of Comparative Zoölogy at Harvard College, Vol. LXV. No. 4.
Bangs, Outram
345 Gutenberg downloadsen2011Difficulty 49 (College)
The Story of Germ Life
Conn, H. W. (Herbert William)
345 Gutenberg downloadsen2004Difficulty 60 (Graduate)
Subspeciation in the Meadow Mouse, Microtus montanus, in Wyoming and Colorado
Anderson, Sydney
343 Gutenberg downloadsen2010Difficulty 50 (College)
Az ember helye a természetben
Lenhossék, Mihály
342 Gutenberg downloadshu2024
The Factors of Organic Evolution
Spencer, Herbert
342 Gutenberg downloadsen2016Difficulty 70 (Academic)
De Usu Ratiocinii Mechanici in Medicina
Boerhaave, Herman
341 Gutenberg downloadsla2005
Descripção de algumas especies novas ou pouco conhecidas de crustaceos e arachnidios de Portugal e possessões portuguezas do ultramar
Capello, Felix Antonio de Brito
341 Gutenberg downloadsfr2010
Section-Cutting A Practical Guide to the Preparation and Mounting of Sections for the Microscope, Special Prominence Being given to the Subject of Animal Sections
Marsh, Sylvester
340 Gutenberg downloadsen2017Difficulty 61 (Academic)
The Christian Foundation, Or, Scientific and Religious Journal, Volume 1, Index, 1880
Various
339 Gutenberg downloadsen2009Difficulty 77 (Expert)
The O. S. U. Naturalist, Vol. 1, No. 1, November, 1900
Ohio State University. Biological Club
339 Gutenberg downloadsen2017Difficulty 56 (Graduate)
The Rocky Mountain Goat
Grant, Madison
339 Gutenberg downloadsen2015Difficulty 57 (Graduate)
Use of the Dead to the Living
Smith, Southwood
339 Gutenberg downloadsen2018Difficulty 67 (Academic)
Studies in Spermatogenesis (Part 1 of 2)
Stevens, N. M. (Nettie Maria)
338 Gutenberg downloadsen2010Difficulty 57 (Graduate)
The Sense of Taste
Hollingworth, Harry L. (Harry Levi) & Poffenberger, Albert T. (Albert Theodore)
338 Gutenberg downloadsen2019Difficulty 69 (Academic)
A New Hylid Frog from Eastern Mexico. University of Kansas Publication, Vol 1, No 15
Taylor, Edward Harrison
337 Gutenberg downloadsen2010Difficulty 62 (Academic)
Food of the Crow, Corvus brachyrhynchos Brehm, in South-central Kansas
Platt, Dwight R.
337 Gutenberg downloadsen2010Difficulty 53 (Graduate)
On the origin of inflammation of the veins and of the causes, consequences, and treatment of purulent deposits
Lee, Henry, M.D.
337 Gutenberg downloadsen2014Difficulty 65 (Academic)
Schenk's Theory: The Determination of Sex
Schenk, Samuel Leopold
337 Gutenberg downloadsen2014Difficulty 59 (Graduate)
The Nautilus. Vol. XXXI, No. 2, October 1917 A Quarterly Journal Devoted to the Interests of Conchologists
Various
337 Gutenberg downloadsen2019Difficulty 52 (Graduate)
The Ohio Naturalist, Vol. I, No. 7, May, 1901
Ohio State University. Biological Club
337 Gutenberg downloadsen2023Difficulty 51 (Graduate)
Educação nova: As bases
Alves dos Santos, Augusto Joaquim
335 Gutenberg downloadspt2012
Mammals of the Grand Mesa, Colorado
Anderson, Sydney
335 Gutenberg downloadsen2010Difficulty 51 (Graduate)
Reise in die Aequinoctial-Gegenden des neuen Continents. Band 4.
Humboldt, Alexander von
335 Gutenberg downloadsde2012
A New Chipmunk (Genus Eutamias) from the Black Hills
White, John A.
334 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Inferences from Haunted Houses and Haunted Men
Harris, J. W. (John William)
334 Gutenberg downloadsen2004Difficulty 50 (College)
The Philosophy of Evolution Together With a Preliminary Essay on The Metaphysical Basis of Science
Carpenter, Stephen H. (Stephen Haskins)
334 Gutenberg downloadsen2009Difficulty 64 (Academic)
Proefnemingen van de particuliere beweeging der spieren in de kikvorsch
Swammerdam, Jan
333 Gutenberg downloadsnl2006
The O. S. U. Naturalist, Vol. 1, No. 2, December, 1900
Ohio State University. Biological Club
333 Gutenberg downloadsen2023Difficulty 52 (Graduate)
A New Doglike Carnivore, Genus Cynarctus, From the Clarendonian, Pliocene, of Texas
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
332 Gutenberg downloadsen2009Difficulty 53 (Graduate)
A New Pocket Mouse (Genus Perognathus) from Kansas
Cockrum, E. Lendell
331 Gutenberg downloadsen2010Difficulty 51 (Graduate)
A Monograph of Odontoglossum
Bateman, Jas. (James)
330 Gutenberg downloadsen2014Difficulty 61 (Academic)
De Rariorum Animalium atque Stirpium Historia
Caius, John
330 Gutenberg downloadsla2008
Geographic Variation in the Harvest Mouse, Reithrodontomys megalotis, On the Central Great Plains And in Adjacent Regions
Jones, J. Knox & Mursaloglu, B.
330 Gutenberg downloadsen2009Difficulty 56 (Graduate)
The Philosophy Which Shows the Physiology of Mesmerism and Explains the Phenomenon of Clairvoyance
Pasley, T. H.
330 Gutenberg downloadsen2015Difficulty 74 (Expert)
Suomen maan Meripedot: maalikuvilla selitetyt
Eurén, Gustaf Erik
329 Gutenberg downloadsfi2005
A New Subspecies of the Fruit-eating Bat, Sturnira ludovici, From Western Mexico
Jones, J. Knox & Phillips, Gary L.
328 Gutenberg downloadsen2010Difficulty 55 (Graduate)
New West Indian Spiders Bulletin of the AMNH, Vol. XXXIII, Art. XLI, pp. 639-642
Banks, Nathan
327 Gutenberg downloadsen2010Difficulty 47 (College)
The Postnatal Development of Two Broods of Great Horned Owls (Bubo virginianus)
Hoffmeister, Donald Frederick & Setzer, Henry W.
327 Gutenberg downloadsen2011Difficulty 51 (Graduate)
The Science of Animal Locomotion (Zoopraxography) An Electro-Photographic Investigation of Consecutive Phases of Animal Movements
Muybridge, Eadweard
327 Gutenberg downloadsen2012Difficulty 64 (Academic)
A New Piñon Mouse (Peromyscus truei) from Durango, Mexico
Finley, Robert B.
326 Gutenberg downloadsen2010Difficulty 57 (Graduate)
Subspeciation in the Meadow Mouse, Microtus pennsylvanicus, in Wyoming, Colorado, and Adjacent Areas
Anderson, Sydney
326 Gutenberg downloadsen2010Difficulty 61 (Academic)
Tentamen Botanicum de Filicum Generibus Dorsiferarum Mémoires de l'Académie Royale des Sciences de Turin vol. 5, 401-422
Smith, James Edward
326 Gutenberg downloadsla2012
The Baculum in the Chipmunks of Western North America
White, John A.
326 Gutenberg downloadsen2010Difficulty 46 (College)
A New Long-eared Myotis (Myotis evotis) From Northeastern Mexico
Baker, Rollin H. (Rollin Harold) & Stains, Howard J.
325 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Humanity to Honey-Bees or, Practical Directions for the Management of Honey-Bees Upon an Improved and Humane Plan, by Which the Lives of Bees May Be Preserved, and Abundance of Honey of a Superior Quality May Be Obtained
Nutt, Thomas
325 Gutenberg downloadsen2018Difficulty 65 (Academic)
The Mammals of Warren Woods, Berrien County, Michigan Occasional Paper of the Museum of Zoology, Number 86
Dice, Lee R. (Lee Raymond)
325 Gutenberg downloadsen2010Difficulty 49 (College)
A New Pocket Gopher (Genus Thomomys), from Eastern Colorado
Hall, E. Raymond (Eugene Raymond)
324 Gutenberg downloadsen2011Difficulty 60 (Graduate)
A New Species of Heteromyid Rodent from the Middle Oligocene of Northeast Colorado with Remarks on the Skull
Galbreath, Edwin C. (Edwin Carter)
324 Gutenberg downloadsen2010Difficulty 57 (Graduate)
Atlas de poche des mammifères de la France, de la Suisse romane et de la Belgique avec leur description, moeurs et organisation
Martin, René
324 Gutenberg downloadsfr2017
Het Leven der Dieren. Deel 3, Hoofdstuk 5: De Amphibiën
Brehm, Alfred Edmund
324 Gutenberg downloadsnl2014
The Book of Shells Containing the Classes Mollusca, Conchifera, Cirrhipeda, Annulata, and Crustacea
Society for Promoting Christian Knowledge (Great Britain). Committee of General Literature and Education
324 Gutenberg downloadsen2019Difficulty 64 (Academic)
Jelly-Fish, Star-Fish, and Sea-Urchins: Being a Research on Primitive Nervous Systems
Romanes, George John
323 Gutenberg downloadsen2014Difficulty 64 (Academic)
A Check-List of the Birds of Idaho
Arvey, M. Dale (Martin Dale)
322 Gutenberg downloadsen2011Difficulty 55 (Graduate)
A New Subspecies of Pocket Mouse from Kansas
Hall, E. Raymond (Eugene Raymond)
322 Gutenberg downloadsen2010Difficulty 57 (Graduate)
De Harmonie van het Dierlijke Leven: De Openbaring van Wetten
Donders, F. C. (Franciscus Cornelis)
321 Gutenberg downloadsnl2005
Description of a New Vespertilionine Bat from Yucatan Author's Edition, extracted from Bulletin of the American Museum of Natural History, Vol. IX, September 28, 1897
Allen, J. A. (Joel Asaph)
321 Gutenberg downloadsen2008Difficulty 53 (Graduate)
Geographic Distribution and Taxonomy of the Chipmunks of Wyoming
White, John A.
320 Gutenberg downloadsen2010Difficulty 50 (College)
Het Leven der Dieren: Hoofdstuk 8: De Vinduikers; Hoofdstuk 9: de Stormvogels
Brehm, Alfred Edmund
320 Gutenberg downloadsnl2010
A study of mushrooms and mushroom spawn
Jacob, Edward Henry
319 Gutenberg downloadsen2023Difficulty 50 (College)
Fishes of the Wakarusa River in Kansas
Deacon, James E. & Metcalf, Artie L.
319 Gutenberg downloadsen2010Difficulty 45 (College)
Jaundice: Its Pathology and Treatment With the Application of Physiological Chemistry to the Detection and Treatment of Diseases of the Liver and Pancreas
Harley, George
319 Gutenberg downloadsen2015Difficulty 69 (Academic)
Treatise on the Anatomy and Physiology of the Mucous Membranes With Illustrative Pathological Observations
Bichat, Xavier
319 Gutenberg downloadsen2016Difficulty 67 (Academic)
Fauna der Nassauischen Mollusken
Kobelt, Wilhelm
318 Gutenberg downloadsde2015
Natural History of the Bell Vireo, Vireo bellii Audubon
Barlow, Jon C.
318 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Two New Pelycosaurs from the Lower Permian of Oklahoma
Fox, Richard C.
317 Gutenberg downloadsen2009Difficulty 59 (Graduate)
Poisonous Snakes of Kansas
Clarke, Robert F. (Robert Francis)
316 Gutenberg downloadsen2019Difficulty 50 (College)
A New Tortoise, Genus Gopherus, From North-central Mexico
Legler, John M.
315 Gutenberg downloadsen2010Difficulty 62 (Academic)
Field Mice as Farm and Orchard Pests
Lantz, David E. (David Ernest)
314 Gutenberg downloadsen2013Difficulty 54 (Graduate)
Pipistrellus cinnamomeus Miller 1902 Referred to the Genus Myotis
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
314 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Μικρά Φυσικά, Τόμος Δεύτερος
Aristotle
314 Gutenberg downloadsel2009
A New Snake of the Genus Geophis From Chihuahua, Mexico
Legler, John M.
312 Gutenberg downloadsen2010Difficulty 63 (Academic)
Journal of Entomology and Zoology, Vol. 06, No. 4, December 1914
Various
311 Gutenberg downloadsen2015Difficulty 53 (Graduate)
A New Pocket Gopher (Thomomys) and A New Spiny Pocket Mouse (Liomys) from Michoacán, Mexico
Hall, E. Raymond (Eugene Raymond) & Villa Ramírez, Bernardo
310 Gutenberg downloadsen2010Difficulty 60 (Graduate)
A New Subspecies of Bat (Myotis velifer) from Southeastern California and Arizona
Vaughan, Terry A.
310 Gutenberg downloadsen2010Difficulty 56 (Graduate)
Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado
Douglas, Charles L.
310 Gutenberg downloadsen2012Difficulty 63 (Academic)
Conspecificity of two pocket mice, Perognathus goldmani and P. artus
Hall, E. Raymond (Eugene Raymond) & Ogilvie, Marilyn Bailey
310 Gutenberg downloadsen2010Difficulty 52 (Graduate)
Schutz- und Trutzbündnisse in der Natur
Bölsche, Wilhelm
310 Gutenberg downloadsde2015
A New Subspecies of Wood Rat (Neotoma mexicana) from Colorado
Finley, Robert B.
309 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Dissertatio inauguralis physico-medica de respiratione quam consensu & auctoritate gratiosissimi medicorum ordinis in universitate patria pro summis in arte medica honoribus & privilegiis doctoralibus rite consequendis....
Bernoulli, Daniel
309 Gutenberg downloadsla2013
Geographic Variation in the Pocket Gopher, Thomomys bottae, in Colorado
Youngman, Phillip M.
309 Gutenberg downloadsen2011Difficulty 57 (Graduate)
Het Leven der Dieren: Deel 2, Hoofdstuk 10: De Stootvogels
Brehm, Alfred Edmund
309 Gutenberg downloadsnl2012
The Botanical Magazine, Vol. 09 Or, Flower-Garden Displayed
Curtis, William
309 Gutenberg downloadsen2011Difficulty 58 (Graduate)
Geographic Variation in the Pocket Gopher, Cratogeomys castanops, in Coahuila, México
Russell, Robert J. & Baker, Rollin H. (Rollin Harold)
308 Gutenberg downloadsen2010Difficulty 64 (Academic)
The Cubomedusæ
Conant, Franklin Story
308 Gutenberg downloadsen2017Difficulty 60 (Graduate)
Geographic Variation in Red-backed Mice (Genus Clethrionomys) of the Southern Rocky Mountain Region
Cockrum, E. Lendell & Fitch, Kenneth Leonard
306 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Ecology of the Opossum on a Natural Area in Northeastern Kansas
Fitch, Henry S. (Henry Sheldon) & Sandidge, Lewis L.
304 Gutenberg downloadsen2011Difficulty 62 (Academic)
Practical Skunk Raising A Book of Information Concerning the Raising of Skunks for Profit
Pratt, William Edwin
304 Gutenberg downloadsen2014Difficulty 40 (High School)
Studies in Spermatogenesis (Part 2 of 2)
Stevens, N. M. (Nettie Maria)
304 Gutenberg downloadsen2010Difficulty 58 (Graduate)
Genera of Leptodactylid Frogs in México
Lynch, John D.
302 Gutenberg downloadsen2010Difficulty 74 (Expert)
Records of Harvest Mice, Reithrodontomys, from Central America, with Description of a New Subspecies from Nicaragua
Anderson, Sydney & Jones, J. Knox
302 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Eugenics as a Factor in the Prevention of Mental Disease
Pollock, Horatio M. (Horatio Milo)
301 Gutenberg downloadsen2011Difficulty 65 (Academic)
De koraal-eilanden: fragment uit het dagboek van een natuuronderzoeker De Aarde en haar Volken, 1875
Darwin, Charles
300 Gutenberg downloadsnl2015
Die Protozoen als Krankheitserreger des Menschen und der Hausthiere Für Ärzte, Thierärzte und Zoologen
Schneidemühl, Georg
300 Gutenberg downloadsde2016
The American Apiculturist. Vol. III. No. 6, June 15, 1885 A Journal Devoted to Scientific and Practical Beekeeping
Various
300 Gutenberg downloadsen2018Difficulty 54 (Graduate)
Additional Records and Extensions of Known Ranges of Mammals from Utah
Durrant, Stephen David & Hansen, Richard M. & Lee, M. Raymond
298 Gutenberg downloadsen2010Difficulty 57 (Graduate)
Experiments on the Nervous System with Opium and Metalline Substances Made Chiefly with the View of Determining the Nature and Effects of Animal Electricity
Monro, Alexander
298 Gutenberg downloadsen2014Difficulty 66 (Academic)
The Tadpoles of Bufo cognatus Say
Smith, Hobart M. (Hobart Muir)
298 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Die krankheiterregenden Bakterien Entstehung, Heilung und Bekämpfung der bakteriellen Infektionskrankheiten des Menschen
Löhlein, Max
297 Gutenberg downloadsde2017
The Protection of Fresh-Water Mussels
Coker, R. E. (Robert Ervin)
297 Gutenberg downloadsen2013Difficulty 65 (Academic)
Pleistocene Soricidae from San Josecito Cave, Nuevo Leon, Mexico
Findley, James S. (James Smith)
296 Gutenberg downloadsen2010Difficulty 58 (Graduate)
The Periodical Cicada, "the 17-year Locust"
United States. Department of Agriculture
296 Gutenberg downloadsen2019Difficulty 51 (Graduate)
The Pigmy Woodrat, Neotoma goldmani, Its Distribution and Systematic Position
Rainey, Dennis G. & Baker, Rollin H. (Rollin Harold)
296 Gutenberg downloadsen2010Difficulty 61 (Academic)
An account of the manner of inoculating for the small pox in the East Indies With some observations on the practice and mode of treating that disease in those parts
Holwell, J. Z. (John Zephaniah)
295 Gutenberg downloadsen2016Difficulty 88 (Specialist)
Two New Moles (Genus Scalopus) from Mexico and Texas
Baker, Rollin H. (Rollin Harold)
295 Gutenberg downloadsen2010Difficulty 56 (Graduate)
The Fern Bulletin, October 1903 A Quarterly Devoted to Ferns
Various
294 Gutenberg downloadsen2018Difficulty 50 (College)
The Virtue and Use of Coffee With Regard to the Plague and Other Infectious Distempers
Bradley, Richard
293 Gutenberg downloadsen2019Difficulty 63 (Academic)
The Hand Phrenologically Considered Being a Glimpse at the Relation of the Mind with the Organisation of the Body
Anonymous
292 Gutenberg downloadsen2016Difficulty 70 (Academic)
Complete Treatise on the mare and foal at the time of delivery, with illustrations. Also on cows and calves, with stallion and mare, when diseased by Gonorrhea (clap) or Pox, also Diarrhea and Costiveness in Colts.
Mitchell, Conrad
291 Gutenberg downloadsen2016Difficulty 49 (College)
Contagious Abortion of Cows
MacNeal, Ward J.
291 Gutenberg downloadsen2011Difficulty 66 (Academic)
Epidemics Examined and Explained: or, Living Germs Proved by Analogy to be a Source of Disease
Grove, John
291 Gutenberg downloadsen2010Difficulty 65 (Academic)
A New Species of Frog (Genus Tomodactylus) from Western México
Webb, Robert G. (Robert Gravem)
290 Gutenberg downloadsen2010Difficulty 62 (Academic)
An Account of the Sore Throat Attended With Ulcers A Disease Which Hath of Late Years Appeared in This City, and in Several Parts of the Nation
Fothergill, John
290 Gutenberg downloadsen2017Difficulty 67 (Academic)
House Flies
Howard, L. O. (Leland Ossian)
290 Gutenberg downloadsen2019Difficulty 56 (Graduate)
Physiology and histology of the Cubomedusæ including Dr. F.S. Conant's notes on the physiology
Berger, E. W. (Edward William)
290 Gutenberg downloadsen2017Difficulty 62 (Academic)
The Methods and Scope of Genetics An inaugural lecture delivered 23 October 1908
Bateson, William
289 Gutenberg downloadsen2016Difficulty 60 (Graduate)
Tadarida femorosacca (Merriam) in Tamaulipas, Mexico
Dalquest, Walter Woelber & Hall, E. Raymond (Eugene Raymond)
288 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Notes on the Mammals of Gogebic and Ontonagon Counties, Michigan, 1920 Occasional Papers of the Museum of Zoology, Number 109
Dice, Lee R. (Lee Raymond) & Sherman, Harley Bakwel
287 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Notes on Diseases of Cattle: Cause, Symptoms and Treatment
Korinek, Charles James
286 Gutenberg downloadsen2019Difficulty 55 (Graduate)
Thoughts on General and Partial Inoculations Containing a translation of two treatises written when the author was at Petersburg, and published there, by Command of her Imperial Majesty, in the Russian Language
Dimsdale, Thomas
285 Gutenberg downloadsen2015Difficulty 67 (Academic)
The Florist and Horticultural Journal, Vol. II. No. 7, July, 1853 A Monthly Magazine of Horticulture, Agriculture, Botany, Agricultural Chemistry, Entomology, &c.
Various
284 Gutenberg downloadsen2018Difficulty 55 (Graduate)
Bees from British Guiana Bulletin of the AMNH, Vol. XXXVIII, Art. XX, pp. 685-690
Cockerell, Theodore D. A. (Theodore Dru Alison)
283 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Florulae Insularum Australium Prodromus
Forster, Georg
283 Gutenberg downloadsla2011
La espressione dei sentimenti dei nostri volatili domestici
Pascal, Teodoro
283 Gutenberg downloadsit2017
A New Bat (Genus Myotis) From Mexico
Dalquest, Walter Woelber & Hall, E. Raymond (Eugene Raymond)
282 Gutenberg downloadsen2010Difficulty 57 (Graduate)
The Systematic Status of Eumeces pluvialis Cope
Smith, Hobart M. (Hobart Muir)
282 Gutenberg downloadsen2011Difficulty 60 (Graduate)
Wintering Bees in Cellars
Phillips, Everett Franklin & Demuth, Geo. S. (George S.)
278 Gutenberg downloadsen2019Difficulty 52 (Graduate)
Disease in captive wild mammals and birds : $b incidence, description, comparison
Fox, Herbert
274 Gutenberg downloadsen2025Difficulty 55 (Graduate)
Nitrogen Bacteria and Legumes With special reference to red clover, cowpeas, soy beans, alfalfa, and sweet clover, on Illinois soils
Hopkins, Cyril G. (Cyril George)
274 Gutenberg downloadsen2018Difficulty 58 (Graduate)
Descriptions of Three New Birds from the Belgian Congo Bulletin of the AMNH , Vol. XXXIV, Art. XVI, pp. 509-513, Oct. 20th, 1915
Chapin, James Paul
272 Gutenberg downloadsen2010Difficulty 49 (College)
The Kansas University Science Bulletin (Vol. I, No. 1)
Various
272 Gutenberg downloadsen2017Difficulty 50 (College)
A New Bat (Genus Pipistrellus) from Northeastern Mexico
Baker, Rollin H. (Rollin Harold)
271 Gutenberg downloadsen2010Difficulty 56 (Graduate)
Memoria sobre a cultura da Urumbeba e sobre criação da Cochonilha
Thiéry de Menonville, Nicolas-Joseph & Berthollet, Claude-Louis & Velloso, José Mariano da Conceição
271 Gutenberg downloadspt2012
Taxonomic Status of Some Mice of The Peromyscus boylii Group in Eastern Mexico, With Description of a New Subspecies
Alvarez, Ticul
271 Gutenberg downloadsen2010Difficulty 52 (Graduate)
A Defence of the Inquiry into Mesmerism & Phrenology chiefly in relation to recent events in Lynn
Armes, William
270 Gutenberg downloadsen2017Difficulty 66 (Academic)
Sphinx Vespiformis: An Essay
Newman, Edward
269 Gutenberg downloadsen2013Difficulty 73 (Expert)
Kasvikon oppisanoja
Lönnrot, Elias
268 Gutenberg downloadsfi2017
Extensions of Known Ranges of Mexican Bats
Anderson, Sydney
265 Gutenberg downloadsen2010Difficulty 53 (Graduate)
The Ohio Journal of Science, Vol. XVI, No. 1, November 1915
Various
265 Gutenberg downloadsen2017Difficulty 50 (College)
Importanza e risultati degli incrociamenti in avicoltura
Pascal, Teodoro
264 Gutenberg downloadsit2018
Le livree dei nostri volatili domestici in rapporto allo sport, alla produttività ed alla rusticità
Pascal, Teodoro
261 Gutenberg downloadsit2019
Influenza
Provincial Board of Health of Ontario
259 Gutenberg downloadsen2019Difficulty 68 (Academic)
New Subspecies of the Rodent Baiomys from Central America University of Kansas Publications, Museum of Natural History
Packard, Robert L. (Robert Lewis)
255 Gutenberg downloadsen2012Difficulty 62 (Academic)
Den Hunting as a Means of Coyote Control
Young, Stanley Paul & Dobyns, Harold Warren
254 Gutenberg downloadsen2015Difficulty 49 (College)
Bananas: Nature's Institution for the Promotion of Laziness
Perry, Edward Wilkin
252 Gutenberg downloadsen2017Difficulty 52 (Graduate)
Het paard : $b in zijne natuurlijke ontwikkeling
Bölsche, Wilhelm
251 Gutenberg downloadsnl2025
A Letter on Suspended Animation containing experiments shewing that it may be safely employed during operations on animals
Hickman, Henry Hill
250 Gutenberg downloadsen2018Difficulty 77 (Expert)
The run
Hay, John
243 Gutenberg downloadsen2025Difficulty 48 (College)
Blonde duinen
Thijsse, Jac. P. (Jacobus Pieter)
225 Gutenberg downloadsnl2025

Pharmacographia A history of the principal drugs of vegetable origin, met with in Great Britain and British India

Origin of Cultivated Plants The International Scientific Series Volume XLVIII

Studies of American Fungi. Mushrooms, Edible, Poisonous, etc.

The Natural History of Pliny, Volume 5 (of 6)

Vegetable Teratology An Account of the Principal Deviations from the Usual Construction of Plants

The Elements of Bacteriological Technique A Laboratory Guide for Medical, Dental, and Technical Students. Second Edition Rewritten and Enlarged.

Life and Letters of Charles Darwin — Volume 1

More Letters of Charles Darwin — Volume 1 A Record of His Work in a Series of Hitherto Unpublished Letters

On the Origin of Species By Means of Natural Selection Or, the Preservation of Favoured Races in the Struggle for Life

The Variation of Animals and Plants Under Domestication, Vol. I.

The Natural History of Pliny, Volume 3 (of 6)

On Growth and Form

Darwin, and After Darwin, Volumes 1 and 3 An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions

On the Origin of Species by Means of Natural Selection or the Preservation of Favoured Races in the Struggle for Life. (2nd edition)

The Notebooks of Leonardo Da Vinci — Complete

The Animal Parasites of Man

The Variation of Animals and Plants under Domestication

Mysteries of Bee-keeping Explained

Evolution, Old & New Or, the Theories of Buffon, Dr. Erasmus Darwin and Lamarck, as compared with that of Charles Darwin

The Evolution of Marriage and of the Family

An introduction to the study of mammals living and extinct

Letters of Asa Gray; Vol. 2

Contributions to the Theory of Natural Selection A Series of Essays

Cattle and Their Diseases Embracing Their History and Breeds, Crossing and Breeding, and Feeding and Management; with the Diseases to Which They Are Subject, and the Remedies Best Adapted to Their Cure

Fossil plants, Vol. 2 : $b A text-book for students of botany and geology

Travels in Peru and India While Superintending the Collection of Chinchona Plants and Seeds in South America, and Their Introduction into India.

Manual of the Trees of North America (Exclusive of Mexico) 2nd ed.

Lichens

The Cambridge natural history, Vol. 02 (of 10)

The Foundations of the Origin of Species Two Essays written in 1842 and 1844

Birds of the Rockies

Insects and Diseases A Popular Account of the Way in Which Insects may Spread or Cause some of our Common Diseases

The Cambridge natural history, Vol. 01 (of 10)

A Manual of Philippine Birds

The Cambridge natural history, Vol. 03 (of 10)

Evolution in Modern Thought

The Medicinal Plants of the Philippines

Handbook of Birmingham Prepared for the Members of the British Association, 1886

The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality

A History of North American Birds; Land Birds; Vol. 3 of 3

Sketches of the Natural History of Ceylon

Makers of British Botany; a collection of biographies by living botanists

A Text-book of Entomology Including the Anatomy, Physiology, Embryology and Metamorphoses of Insects for Use in Agricultural and Technical Schools and Colleges as Well as by the Working Entomologist

Zoölogische Philosophie Of beschouwingen over de Natuurlijke Historie der dieren etc.

The Dawn of Reason; or, Mental Traits in the Lower Animals

Sir Jagadis Chunder Bose, His Life and Speeches

An Introduction to Entomology: Vol. 3 or Elements of the Natural History of the Insects

The works of Francis Maitland Balfour, Volume 2 (of 4) : $b A treatise on comparative embryology: Invertebrata

The Stock-Feeder's Manual the chemistry of food in relation to the breeding and feeding of live stock

The Cambridge natural history, Vol. 07 (of 10)

Cassell's Natural History, Vol. 1 (of 6)

The Insect World Being a Popular Account of the Orders of Insects; Together with a Description of the Habits and Economy of Some of the Most Interesting Species

Outlines of Dairy Bacteriology, 8th edition A Concise Manual for the Use of Students in Dairying

An Introduction to Entomology: Vol. 4 or Elements of the Natural History of the Insects

Fossil plants, Vol. 3 : $b A text-book for students of botany and geology

The Microscope. Its History, Construction, and Application 15th ed. Being a familiar introduction to the use of the instrument, and the study of microscopical science

Fossil plants, Vol. 1 : $b [A text-book] for students of botany and geology

The Expression of the Emotions in Man and Animals

The reason why : $b a careful collection of many hundreds of reasons for things which, though generally believed, are imperfectly understood. A book of condensed scientific knowledge for the million

The Origin of Species by Means of Natural Selection Or, the Preservation of Favoured Races in the Struggle for Life, 6th Edition

The Cambridge natural history, Vol. 04 (of 10)

Delineations of the Ox Tribe: The Natural History of Bulls, Bisons, and Buffaloes. Exhibiting all the Known Species and the More Remarkable Varieties of the Genus Bos.

The Cambridge natural history, Vol. 06 (of 10)

Man And His Ancestor: A Study In Evolution

Aristotle's History of Animals In Ten Books

The life of Jean Henri Fabre, the entomologist, 1823-1910

The book of wonders : $b gives plain and simple answers to the thousands of everyday questions that are asked and which all should be able to, but cannot answer...

First course in biology

Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, First Part: Porulosa (Spumellaria and Acantharia) Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76, Vol. XVIII

The Voyage of the Beagle

Species Plantarum, Sections IV-V

History of Botany (1530-1860)

The grapes of New York

Darwin

Journal of Researches into the Natural History and Geology of the Countries Visited During the Voyage Round the World of H.M.S. Beagle Under the Command of Captain Fitz Roy, R.N.

Snakes: Curiosities and Wonders of Serpent Life

An Elementary Study of Insects

The works of Francis Maitland Balfour, Volume 3 (of 4) : $b A treatise on comparative embryology: Vertebrata

The Sea and Its Living Wonders A Popular Account of the Marvels of the Deep and of the Progress of Martime Discovery from the Earliest Ages to the Present Time

Himalayan Journals — Complete Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.