Curated Shelf

Biology

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

1556 WorksDrawn from Project Gutenberg Bookshelf #669

On the Origin of Species By Means of Natural Selection Or, the Preservation of Favoured Races in the Struggle for Life
Darwin, Charles
21,755 Gutenberg downloadsen1998Difficulty 61 (Academic)
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
14,811 Gutenberg downloadsen2013Difficulty 65 (Academic)
The Natural History of Pliny, Volume 3 (of 6)
Pliny, the Elder
13,311 Gutenberg downloadsen2019Difficulty 38 (High School)
Life and Letters of Charles Darwin — Volume 1
Darwin, Charles
13,086 Gutenberg downloadsen2000Difficulty 54 (Graduate)
The Notebooks of Leonardo Da Vinci — Complete
Leonardo, da Vinci
12,822 Gutenberg downloadsen2004Difficulty 52 (Graduate)
The Natural History of Pliny, Volume 5 (of 6)
Pliny, the Elder
11,098 Gutenberg downloadsen2019Difficulty 50 (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
8,822 Gutenberg downloadsen2013Difficulty 64 (Academic)
The Origin of Species by Means of Natural Selection Or, the Preservation of Favoured Races in the Struggle for Life, 6th Edition
Darwin, Charles
6,846 Gutenberg downloadsen1999Difficulty 65 (Academic)
An Introduction to Entomology: Vol. 3 or Elements of the Natural History of the Insects
Kirby, William & Spence, William
6,216 Gutenberg downloadsen2013Difficulty 61 (Academic)
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
6,104 Gutenberg downloadsen2025Difficulty 48 (College)
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
5,344 Gutenberg downloadsen2022Difficulty 66 (Academic)
Fossil plants, Vol. 2 : $b A text-book for students of botany and geology
Seward, A. C. (Albert Charles)
5,323 Gutenberg downloadsen2022Difficulty 63 (Academic)
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
5,134 Gutenberg downloadsen2012Difficulty 60 (Graduate)
Vegetable Teratology An Account of the Principal Deviations from the Usual Construction of Plants
Masters, Maxwell T. (Maxwell Tylden)
4,393 Gutenberg downloadsen2007Difficulty 61 (Academic)
Origin of Cultivated Plants The International Scientific Series Volume XLVIII
Candolle, Alphonse de
4,337 Gutenberg downloadsen2014Difficulty 62 (Academic)
The Descent of Man, and Selection in Relation to Sex
Darwin, Charles
4,262 Gutenberg downloadsen2000Difficulty 69 (Academic)
The Voyage of the Beagle
Darwin, Charles
4,232 Gutenberg downloadsen1997Difficulty 56 (Graduate)
Grundzüge der Paläontologie (Paläozoologie). 1. Abteilung: Invertebrata.
Zittel, Karl Alfred von
3,781 Gutenberg downloadsde2023
Micrographia Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses with Observations and Inquiries Thereupon
Hooke, Robert
3,604 Gutenberg downloadsen2005Difficulty 76 (Expert)
Flora von Deutschland Ein Hilfsbuch zum Bestimmen der zwischen den deutschen Meeren und den Alpen wildwachsenden und angebauten Pflanzen
Schmeil, O. (Otto) & Fitschen, Jost
3,444 Gutenberg downloadsde2019
The Expression of the Emotions in Man and Animals
Darwin, Charles
3,331 Gutenberg downloadsen1998Difficulty 64 (Academic)
On Growth and Form
Thompson, D'Arcy Wentworth
3,320 Gutenberg downloadsen2017Difficulty 53 (Graduate)
The Evolution of Man
Haeckel, Ernst
3,303 Gutenberg downloadsen2005Difficulty 49 (College)
Identification of the Larger Fungi
Watling, Roy
2,950 Gutenberg downloadsen2019Difficulty 62 (Academic)
The Medicinal Plants of the Philippines
Pardo de Tavera, T. H. (Trinidad Hermenegildo)
2,810 Gutenberg downloadsen2008Difficulty 67 (Academic)
Clever Hans (The Horse of Mr. Von Osten) A contribution to experimental animal and human psychology
Pfungst, Oskar
2,785 Gutenberg downloadsen2010Difficulty 58 (Graduate)
Manual of the Trees of North America (Exclusive of Mexico) 2nd ed.
Sargent, Charles Sprague
2,733 Gutenberg downloadsen2014Difficulty 78 (Expert)
Form and Function: A Contribution to the History of Animal Morphology
Russell, E. S. (Edward Stuart)
2,731 Gutenberg downloadsen2007Difficulty 59 (Graduate)
Studies of American Fungi. Mushrooms, Edible, Poisonous, etc.
Atkinson, George Francis
2,721 Gutenberg downloadsen2008Difficulty 50 (College)
A text-book of veterinary anatomy
Sisson, Septimus
2,718 Gutenberg downloadsen2025Difficulty 76 (Expert)
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
2,623 Gutenberg downloadsen2007Difficulty 73 (Expert)
An Introduction to Entomology: Vol. 4 or Elements of the Natural History of the Insects
Kirby, William & Spence, William
2,598 Gutenberg downloadsen2013Difficulty 68 (Academic)
Letters of Asa Gray; Vol. 2
Gray, Asa
2,559 Gutenberg downloadsen2017Difficulty 47 (College)
More Letters of Charles Darwin — Volume 1 A Record of His Work in a Series of Hitherto Unpublished Letters
Darwin, Charles
2,535 Gutenberg downloadsen2001Difficulty 50 (College)
The Autobiography of Charles Darwin
Darwin, Charles
2,507 Gutenberg downloadsen1999Difficulty 53 (Graduate)
Mysteries of Bee-keeping Explained
Quinby, M. (Moses)
2,500 Gutenberg downloadsen2008Difficulty 78 (Expert)
De afstamming van den mensch en de seksueele teeltkeus, deel 2 (van 2)
Darwin, Charles
2,407 Gutenberg downloadsnl2024
The Animal Parasites of Man
Fantham, Harold Benjamin & Braun, Max & Stephens, J. W. W. (John William Watson) & Theobald, Fred. V. (Frederick Vincent)
2,395 Gutenberg downloadsen2018Difficulty 67 (Academic)
Outlines of Dairy Bacteriology, 8th edition A Concise Manual for the Use of Students in Dairying
Russell, H. L. (Harry Luman)
2,311 Gutenberg downloadsen2009Difficulty 62 (Academic)
Explanation of Terms Used in Entomology
Smith, John Bernhard
2,196 Gutenberg downloadsen2007Difficulty 57 (Graduate)
Herbal simples approved for modern uses of cure
Fernie, William Thomas
2,192 Gutenberg downloadsen2006Difficulty 54 (Graduate)
Mutual Aid: A Factor of Evolution
Kropotkin, Petr Alekseevich, kniaz
2,111 Gutenberg downloadsen2003Difficulty 73 (Expert)
De Wereld vóór de schepping van den mensch
Flammarion, Camille
2,079 Gutenberg downloadsnl2006
The Story-book of Science
Fabre, Jean-Henri
2,037 Gutenberg downloadsen2018Difficulty 43 (College)
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
2,027 Gutenberg downloadsen2003Difficulty 66 (Academic)
An Introduction to Entomology: Vol. 1 or Elements of the Natural History of the Insects
Kirby, William & Spence, William
2,005 Gutenberg downloadsen2013Difficulty 74 (Expert)
The Cambridge natural history, Vol. 01 (of 10)
Hartog, Marcus & Hickson, Sydney J. (Sydney John) & MacBride, E. W. (Ernest William) & Sollas, Igerna Brünhilda Johnson
2,000 Gutenberg downloadsen2023Difficulty 71 (Expert)
Evolution in Modern Thought
Unknown
1,953 Gutenberg downloadsen2007Difficulty 73 (Expert)
Applied Eugenics
Popenoe, Paul & Johnson, Roswell H. (Roswell Hill)
1,882 Gutenberg downloadsen2006Difficulty 55 (Graduate)
The elements of bacteriological technique : $b a laboratory guide for medical, dental, and technical students
Eyre, J. W. H. (John William Henry)
1,776 Gutenberg downloadsen2009Difficulty 59 (Graduate)
Cosmos: A Sketch of the Physical Description of the Universe, Vol. 1
Humboldt, Alexander von
1,763 Gutenberg downloadsen2005Difficulty 67 (Academic)
The Outline of Science, Vol. 1 (of 4) A Plain Story Simply Told
Thomson, J. Arthur (John Arthur)
1,762 Gutenberg downloadsen2007Difficulty 66 (Academic)
Birds of the Rockies
Keyser, Leander S. (Leander Sylvester)
1,730 Gutenberg downloadsen2008Difficulty 58 (Graduate)
The Evolution of Marriage and of the Family
Letourneau, Ch. (Charles)
1,691 Gutenberg downloadsen2022Difficulty 61 (Academic)
Evolution, Old & New Or, the Theories of Buffon, Dr. Erasmus Darwin and Lamarck, as compared with that of Charles Darwin
Butler, Samuel
1,663 Gutenberg downloadsen2007Difficulty 57 (Graduate)
An introduction to the study of mammals living and extinct
Flower, William Henry & Lydekker, Richard
1,655 Gutenberg downloadsen2025Difficulty 77 (Expert)
Aristotle's History of Animals In Ten Books
Aristotle
1,644 Gutenberg downloadsen2019Difficulty 55 (Graduate)
Lamarck, the Founder of Evolution: His Life and Work
Packard, A. S. (Alpheus Spring)
1,635 Gutenberg downloadsen2007Difficulty 58 (Graduate)
Vestiges of the Natural History of Creation
Chambers, Robert
1,616 Gutenberg downloadsen2004Difficulty 66 (Academic)
The Foundations of the Origin of Species Two Essays written in 1842 and 1844
Darwin, Charles
1,612 Gutenberg downloadsen2007Difficulty 56 (Graduate)
The Formation of Vegetable Mould Through the Action of Worms With Observations on Their Habits
Darwin, Charles
1,602 Gutenberg downloadsen2000Difficulty 63 (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)
1,595 Gutenberg downloadsen2021Difficulty 63 (Academic)
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)
1,592 Gutenberg downloadsen2009Difficulty 47 (College)
Studies in the History and Method of Science, vol. 1 (of 2)
Unknown
1,589 Gutenberg downloadsen2014Difficulty 57 (Graduate)
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
1,566 Gutenberg downloadsen2017Difficulty 62 (Academic)
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.
1,562 Gutenberg downloadsen2016Difficulty 54 (Graduate)
Identifying Hardwoods Growing on Pine Sites
Brown, Clair A. (Clair Alan) & Grelen, Harold E.
1,558 Gutenberg downloadsen2021Difficulty 54 (Graduate)
The Power of Movement in Plants
Darwin, Charles & Darwin, Francis, Sir
1,556 Gutenberg downloadsen2004Difficulty 70 (Academic)
The Descent of Man and Selection in Relation to Sex, Vol. I
Darwin, Charles
1,555 Gutenberg downloadsen2011Difficulty 65 (Academic)
The works of Francis Maitland Balfour, Volume 2 (of 4) : $b A treatise on comparative embryology: Invertebrata
Balfour, Francis M. (Francis Maitland)
1,551 Gutenberg downloadsen2014Difficulty 64 (Academic)
The Science of Fingerprints: Classification and Uses
United States. Federal Bureau of Investigation
1,536 Gutenberg downloadsen2006Difficulty 61 (Academic)
Evidence as to Man's Place in Nature
Huxley, Thomas Henry
1,530 Gutenberg downloadsen2001Difficulty 56 (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
1,530 Gutenberg downloadsen2014Difficulty 79 (Expert)
The Variation of Animals and Plants Under Domestication, Volume II (of 2)
Darwin, Charles
1,524 Gutenberg downloadsen2009Difficulty 73 (Expert)
The Variation of Animals and Plants Under Domestication, Vol. I.
Darwin, Charles
1,521 Gutenberg downloadsen2008Difficulty 67 (Academic)
A History of North American Birds; Land Birds; Vol. 1 of 3
Baird, Spencer Fullerton & Brewer, T. M. (Thomas Mayo) & Ridgway, Robert
1,517 Gutenberg downloadsen2017Difficulty 66 (Academic)
The Biotic Associations of Cockroaches
Roth, Louis M. (Louis Marcus) & Willis, Edwin R.
1,503 Gutenberg downloadsen2014Difficulty 71 (Expert)
Galen: On the Natural Faculties
Galen
1,498 Gutenberg downloadsen2013Difficulty 65 (Academic)
The Variation of Animals and Plants under Domestication
Darwin, Charles
1,496 Gutenberg downloadsen2002Difficulty 86 (Specialist)
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
1,491 Gutenberg downloadsen2018Difficulty 58 (Graduate)
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
1,461 Gutenberg downloadsen2020Difficulty 67 (Academic)
Lehrbuch der Botanik für Hochschulen
Strasburger, Eduard & Noll, Fritz & Schenck, H. (Heinrich) & Schimper, A. F. W. (Andreas Franz Wilhelm)
1,460 Gutenberg downloadsde2020
The Life of the Bee
Maeterlinck, Maurice
1,459 Gutenberg downloadsen2003Difficulty 60 (Graduate)
Inquiries into human faculty and its development
Galton, Francis
1,458 Gutenberg downloadsen2004Difficulty 79 (Expert)
Fossil plants, Vol. 3 : $b A text-book for students of botany and geology
Seward, A. C. (Albert Charles)
1,427 Gutenberg downloadsen2025Difficulty 64 (Academic)
Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 1
Humboldt, Alexander von & Bonpland, Aimé
1,417 Gutenberg downloadsen2004Difficulty 55 (Graduate)
New Zealand Moths and Butterflies (Macro-Lepidoptera)
Hudson, G. V. (George Vernon)
1,403 Gutenberg downloadsen2013Difficulty 60 (Graduate)
The Common Spiders of the United States
Emerton, J. H. (James Henry)
1,402 Gutenberg downloadsen2013Difficulty 45 (College)
Anatomy of the Cat
Reighard, Jacob & Jennings, H. S. (Herbert Spencer)
1,395 Gutenberg downloadsen2018Difficulty 52 (Graduate)
On the mode of communication of cholera
Snow, John
1,391 Gutenberg downloadsen2024Difficulty 58 (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
1,389 Gutenberg downloadsen2001Difficulty 63 (Academic)
An Introduction to Entomology: Vol. 2 or Elements of the Natural History of the Insects
Kirby, William & Spence, William
1,372 Gutenberg downloadsen2013Difficulty 61 (Academic)
American Weasels
Hall, E. Raymond (Eugene Raymond)
1,371 Gutenberg downloadsen2013Difficulty 63 (Academic)
Island Life; Or, The Phenomena and Causes of Insular Faunas and Floras
Wallace, Alfred Russel
1,357 Gutenberg downloadsen2010Difficulty 89 (Specialist)
A conchological manual
Sowerby, G. B. (George Brettingham)
1,353 Gutenberg downloadsen2013Difficulty 64 (Academic)
A History of North American Birds; Land Birds; Vol. 3 of 3
Baird, Spencer Fullerton & Brewer, T. M. (Thomas Mayo) & Ridgway, Robert
1,348 Gutenberg downloadsen2017Difficulty 59 (Graduate)
Lichens
Smith, Annie Lorrain
1,345 Gutenberg downloadsen2020Difficulty 52 (Graduate)
Lay Sermons, Addresses and Reviews
Huxley, Thomas Henry
1,344 Gutenberg downloadsen2005Difficulty 65 (Academic)
Insectivorous Plants
Darwin, Charles
1,342 Gutenberg downloadsen2004Difficulty 63 (Academic)
Insects and Diseases A Popular Account of the Way in Which Insects may Spread or Cause some of our Common Diseases
Doane, Rennie Wilbur
1,339 Gutenberg downloadsen2009Difficulty 58 (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
1,333 Gutenberg downloadsen2008Difficulty 55 (Graduate)
The Cambridge natural history, Vol. 08 (of 10)
Gadow, Hans
1,332 Gutenberg downloadsen2024Difficulty 63 (Academic)
The Naturalist on the River Amazons
Bates, Henry Walter
1,332 Gutenberg downloadsen2000Difficulty 67 (Academic)
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)
1,325 Gutenberg downloadsen2009Difficulty 53 (Graduate)
An Elementary Study of Insects
Haseman, Leonard
1,323 Gutenberg downloadsen2007Difficulty 51 (Graduate)
Life and Letters of Charles Darwin — Volume 2
Darwin, Charles
1,321 Gutenberg downloadsen2000Difficulty 53 (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
1,321 Gutenberg downloadsen2023Difficulty 74 (Expert)
American Forest Trees
Gibson, Henry H.
1,320 Gutenberg downloadsen2013Difficulty 50 (College)
The Cambridge natural history, Vol. 10 (of 10)
Beddard, Frank E. (Frank Evers)
1,320 Gutenberg downloadsen2012Difficulty 61 (Academic)
The Cambridge natural history, Vol. 04 (of 10)
Smith, Geoffrey & Thompson, D'Arcy Wentworth & Warburton, Cecil & Weldon, Walter Frank Raphael & Woods, Henry
1,316 Gutenberg downloadsen2023Difficulty 72 (Expert)
The Life of Crustacea
Calman, W. T. (William Thomas)
1,315 Gutenberg downloadsen2012Difficulty 51 (Graduate)
A system of practical medicine. By American authors. Vol. 1 : $b Pathology and general diseases
Unknown
1,310 Gutenberg downloadsen2012Difficulty 63 (Academic)
The Hunting Wasps
Fabre, Jean-Henri
1,304 Gutenberg downloadsen2022Difficulty 57 (Graduate)
The Cambridge natural history, Vol. 07 (of 10)
Boulenger, George Albert & Bridge, T. W. (Thomas William) & Herdman, W. A. (William Abbott), Sir
1,301 Gutenberg downloadsen2024Difficulty 76 (Expert)
The Elements of Botany, For Beginners and For Schools
Gray, Asa
1,298 Gutenberg downloadsen2010Difficulty 57 (Graduate)
An Introduction to the History of Science
Libby, Walter
1,282 Gutenberg downloadsen2012Difficulty 62 (Academic)
The Homing Pigeon
United States. Army. Signal Corps & United States. War Department
1,271 Gutenberg downloadsen2017Difficulty 51 (Graduate)
The Journal of a Disappointed Man
Barbellion, W. N. P.
1,268 Gutenberg downloadsen2012Difficulty 42 (College)
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
1,266 Gutenberg downloadsen2009Difficulty 57 (Graduate)
Butterflies and Moths (British)
Furneaux, William S.
1,262 Gutenberg downloadsen2010Difficulty 44 (College)
Charles Darwin: His Life Told in an Autobiographical Chapter, and in a Selected Series of His Published Letters
Darwin, Charles
1,249 Gutenberg downloadsen2012Difficulty 53 (Graduate)
The Prolongation of Life: Optimistic Studies
Metchnikoff, Elie
1,231 Gutenberg downloadsen2016Difficulty 58 (Graduate)
Sir Jagadis Chunder Bose, His Life and Speeches
Bose, Jagadis Chandra
1,227 Gutenberg downloadsen2007Difficulty 65 (Academic)
The Life of the Spider
Fabre, Jean-Henri
1,225 Gutenberg downloadsen1999Difficulty 52 (Graduate)
Man, Past and Present
Keane, A. H. (Augustus Henry)
1,220 Gutenberg downloadsen2011Difficulty 60 (Graduate)
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
1,217 Gutenberg downloadsen2014Difficulty 55 (Graduate)
Mammals of Washington, Volume 2 University of Kansas Publications Museum of Natural History
Dalquest, Walter Woelber
1,216 Gutenberg downloadsen2016Difficulty 52 (Graduate)
Biographies of distinguished scientific men. First series
Arago, F. (François)
1,209 Gutenberg downloadsen2005Difficulty 52 (Graduate)
The Life of the Fly; With Which are Interspersed Some Chapters of Autobiography
Fabre, Jean-Henri
1,206 Gutenberg downloadsen2002Difficulty 54 (Graduate)
Fabre's Book of Insects
Fabre, Jean-Henri
1,195 Gutenberg downloadsen2021Difficulty 43 (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
1,193 Gutenberg downloadsen2009Difficulty 60 (Graduate)
Elementary Botany
Atkinson, George Francis
1,191 Gutenberg downloadsen2021Difficulty 53 (Graduate)
The Cambridge natural history, Vol. 09 (of 10)
Evans, A. H. (Arthur Humble)
1,186 Gutenberg downloadsen2024Difficulty 59 (Graduate)
The Organism as a Whole, from a Physicochemical Viewpoint
Loeb, Jacques
1,186 Gutenberg downloadsen2014Difficulty 68 (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
1,181 Gutenberg downloadsen2007Difficulty 67 (Academic)
The Ocean World: Being a Description of the Sea and Its Living Inhabitants.
Figuier, Louis
1,181 Gutenberg downloadsen2014Difficulty 56 (Graduate)
A Guide to the Study of Fishes, Volume 1 (of 2)
Jordan, David Starr
1,180 Gutenberg downloadsen2014Difficulty 66 (Academic)
Natural History of Cottonmouth Moccasin, Agkistrodon piscovorus (Reptilia)
Burkett, Ray D.
1,180 Gutenberg downloadsen2011Difficulty 63 (Academic)
The Book of the Pearl The history, art, science, and industry of the queen of gems
Kunz, George Frederick & Stevenson, Charles Hugh
1,179 Gutenberg downloadsen2020Difficulty 64 (Academic)
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
1,176 Gutenberg downloadsen2012Difficulty 55 (Graduate)
The Dawn of Reason; or, Mental Traits in the Lower Animals
Weir, James, Jr.
1,175 Gutenberg downloadsen2007Difficulty 70 (Academic)
Man's Place in Nature, and Other Essays
Huxley, Thomas Henry
1,173 Gutenberg downloadsen2012Difficulty 65 (Academic)
Encyclopaedia Britannica, 11th Edition, "Echinoderma" to "Edward, prince of Wales" Volume 8, Slice 10
Various
1,169 Gutenberg downloadsen2011Difficulty 65 (Academic)
Handbook of Medical Entomology
Riley, William A. (William Albert) & Johannsen, O. A. (Oskar Augustus)
1,169 Gutenberg downloadsen2010Difficulty 57 (Graduate)
The Riddle of the Universe at the close of the nineteenth century
Haeckel, Ernst
1,169 Gutenberg downloadsen2013Difficulty 72 (Expert)
History of the Conflict Between Religion and Science
Draper, John William
1,168 Gutenberg downloadsen1998Difficulty 62 (Academic)
The Fundamentals of Bacteriology
Morrey, Charles Bradfield
1,161 Gutenberg downloadsen2013Difficulty 67 (Academic)
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
1,158 Gutenberg downloadsen2018Difficulty 64 (Academic)
The pears of New York
Hedrick, U. P.
1,153 Gutenberg downloadsen2014Difficulty 58 (Graduate)
Makers of British Botany; a collection of biographies by living botanists
Unknown
1,152 Gutenberg downloadsen2014Difficulty 61 (Academic)
The Cambridge natural history, Vol. 05 (of 10)
Sedgwick, Adam & Sharp, David & Sinclair, F. G. (Frederick Granville)
1,152 Gutenberg downloadsen2023Difficulty 66 (Academic)
The Mason-Bees
Fabre, Jean-Henri
1,150 Gutenberg downloadsen2001Difficulty 51 (Graduate)
Langstroth on the Hive and the Honey-Bee: A Bee Keeper's Manual
Langstroth, L. L. (Lorenzo Lorraine)
1,146 Gutenberg downloadsen2008Difficulty 44 (College)
Man And His Ancestor: A Study In Evolution
Morris, Charles
1,143 Gutenberg downloadsen2009Difficulty 58 (Graduate)
Darwinism (1889) An exposition of the theory of natural selection, with some of its applications
Wallace, Alfred Russel
1,142 Gutenberg downloadsen2005Difficulty 82 (Specialist)
Falling in Love; With Other Essays on More Exact Branches of Science
Allen, Grant
1,142 Gutenberg downloadsen2005Difficulty 64 (Academic)
Himalayan Journals — Complete Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.
Hooker, Joseph Dalton
1,135 Gutenberg downloadsen2004Difficulty 99 (Quantum Electrodynamics)
The Anatomy of the Human Peritoneum and Abdominal Cavity Considered from the Standpoint of Development and Comparative Anatomy
Huntington, George S. (George Sumner)
1,134 Gutenberg downloadsen2013Difficulty 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)
1,131 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Fossil plants, Vol. 1 : $b [A text-book] for students of botany and geology
Seward, A. C. (Albert Charles)
1,130 Gutenberg downloadsen2022Difficulty 57 (Graduate)
Artistic Anatomy of Animals
Cuyer, Édouard
1,128 Gutenberg downloadsen2011Difficulty 54 (Graduate)
How to Use the Popular Science Library; History of Science; General Index
Serviss, Garrett Putman & Selwyn-Brown, Arthur
1,128 Gutenberg downloadsen2016Difficulty 64 (Academic)
Zoonomia; Or, the Laws of Organic Life, Vol. I
Darwin, Erasmus
1,128 Gutenberg downloadsen2005Difficulty 64 (Academic)
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A Journey in Brazil
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Unknown
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Unknown
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Natural Wonders
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Student's Hand-book of Mushrooms of America, Edible and Poisonous
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The Natural History of the Varieties of Man
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The Progress of the Century
Unknown
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Elementary Zoology, Second Edition
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Rollo's Experiments
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A Civic Biology, Presented in Problems
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The Moths of the British Isles, First Series Comprising the Families Sphingidæ to Noctuidæ
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Nature's Teachings: Human Invention Anticipated by Nature
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Autobiography and Selected Essays
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The Romance of Plant Life Interesting Descriptions of the Strange and Curious in the Plant World
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Our Domestic Birds: Elementary Lessons in Aviculture
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Zoölogy: The Science of Animal Life Popular Science Library, Volume XII (of 16), P. F. Collier & Son Company, 1922
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Darwin and Modern Science
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Insects and Diseases of Trees in the South
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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.
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Species Plantarum, Sections I-III
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Experiments on Animals
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Scientific American Supplement, No. 561, October 2, 1886
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Collected Essays, Volume V Science and Christian Tradition: Essays
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On Molecular and Microscopic Science, Volume 2 (of 2)
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The Genus Pinus
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Zoological Illustrations, Volume 2 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
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The History of Insects
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Nests and Eggs of Birds of the United States Illustrated
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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
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The Biology, Physiology and Sociology of Reproduction Also Sexual Hygiene with Special Reference to the Male
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Scientific American Supplement, No. 595, May 28, 1887
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Scurvy, Past and Present
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The Minds and Manners of Wild Animals: A Book of Personal Observations
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Argentine Ornithology, Volume 2 (of 2) A descriptive catalogue of the birds of the Argentine Republic.
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Mental Evolution in Man: Origin of Human Faculty
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Trees of the Northern United States Their Study, Description and Determination
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Appletons' Popular Science Monthly, December 1899 Vol. LVI, November, 1899 to April, 1900
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The Life of the Caterpillar
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865 Gutenberg downloadsen2021Difficulty 51 (Graduate)
The Structure and Life-history of the Cockroach (Periplaneta orientalis) An Introduction to the Study of Insects
Miall, L. C. (Louis Compton) & Denny, Alfred
865 Gutenberg downloadsen2016Difficulty 58 (Graduate)
Every Girl's Book
Butler, George Frank
864 Gutenberg downloadsen2009Difficulty 41 (College)
The Snakes of Europe
Boulenger, George Albert
862 Gutenberg downloadsen2014Difficulty 63 (Academic)
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)
861 Gutenberg downloadsen2010Difficulty 63 (Academic)
The Pigmy Woodrat, Neotoma goldmani, Its Distribution and Systematic Position
Rainey, Dennis G. & Baker, Rollin H. (Rollin Harold)
860 Gutenberg downloadsen2010Difficulty 61 (Academic)
North American Recent Soft-Shelled Turtles (Family Trionychidae)
Webb, Robert G. (Robert Gravem)
857 Gutenberg downloadsen2012Difficulty 71 (Expert)
Dinosaurs, with Special Reference to the American Museum Collections
Matthew, William Diller
856 Gutenberg downloadsen2006Difficulty 59 (Graduate)
Life histories of North American shore birds, Part 1 (of 2)
Bent, Arthur Cleveland
855 Gutenberg downloadsen2014Difficulty 62 (Academic)
Monism as Connecting Religion and Science A Man of Science
Haeckel, Ernst
854 Gutenberg downloadsen2005Difficulty 74 (Expert)
The Natural Philosophy of Love
Gourmont, Remy de
853 Gutenberg downloadsen2014Difficulty 56 (Graduate)
De l'origine des espèces
Darwin, Charles
852 Gutenberg downloadsfr2004
On the Origin and Metamorphoses of Insects
Lubbock, John, Sir
852 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Structure and functions of the body : $b a hand-book of anatomy and physiology for nurses and others desiring a practical knowledge of the subject
Fiske, Annette
852 Gutenberg downloadsen2021Difficulty 66 (Academic)
The romance of natural history, second series
Gosse, Philip Henry
850 Gutenberg downloadsen2010Difficulty 76 (Expert)
Darwin, and After Darwin, Volume 2 of 3 Post-Darwinian Questions: Heredity and Utility
Romanes, George John
848 Gutenberg downloadsen2011Difficulty 64 (Academic)
The Avifauna of Micronesia, Its Origin, Evolution, and Distribution
Baker, Rollin H. (Rollin Harold)
848 Gutenberg downloadsen2013Difficulty 61 (Academic)
The Harvest of the Sea A contribution to the natural and economic history of the British food fishes
Bertram, James Glass
848 Gutenberg downloadsen2020Difficulty 66 (Academic)
Zoological Illustrations, Volume 3 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
845 Gutenberg downloadsen2012Difficulty 60 (Graduate)
Fruits of the Hawaiian Islands
Wilder, Gerrit Parmile
844 Gutenberg downloadsen2013Difficulty 52 (Graduate)
The Moths of the British Isles, Second Series Comprising the Families Noctuidæ to Hepialidæ
South, Richard
844 Gutenberg downloadsen2013Difficulty 50 (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
842 Gutenberg downloadsen2004Difficulty 61 (Academic)
Botany: The Science of Plant Life
Taylor, Norman
841 Gutenberg downloadsen2015Difficulty 56 (Graduate)
Syndrome
Hoover, Thomas
841 Gutenberg downloadsen2010Difficulty 42 (College)
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
841 Gutenberg downloadsen2014Difficulty 58 (Graduate)
The Nursery-Book: A Complete Guide to the Multiplication and Pollination of Plants
Bailey, L. H. (Liberty Hyde)
841 Gutenberg downloadsen2015Difficulty 50 (College)
A Monograph on the Sub-class Cirripedia (Volume 1 of 2) The Lepadidae; Or, Pedunculated Cirripedes
Darwin, Charles
840 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Text book of veterinary medicine, Volume 4 (of 5)
Law, James
840 Gutenberg downloadsen2024Difficulty 69 (Academic)
A History of Science — Volume 4
Williams, Henry Smith & Williams, Edward Huntington
839 Gutenberg downloadsen1999Difficulty 68 (Academic)
An elementary manual of New Zealand entomology : $b being an introduction to the study of our native insects
Hudson, G. V. (George Vernon)
838 Gutenberg downloadsen2013Difficulty 54 (Graduate)
Birds in Flight
Pycraft, W. P. (William Plane)
838 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Darwiniana; Essays and Reviews Pertaining to Darwinism
Gray, Asa
838 Gutenberg downloadsen2004Difficulty 69 (Academic)
Appletons' Popular Science Monthly, February 1900 Vol. 56, November, 1899 to April, 1900
Various
837 Gutenberg downloadsen2014Difficulty 62 (Academic)
The Child's Book of Nature Three parts in one
Hooker, Worthington
837 Gutenberg downloadsen2018Difficulty 36 (High School)
A Treatise on Physiology and Hygiene For Educational Institutions and General Readers
Hutchison, Joseph C. (Joseph Chrisman)
833 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Birds useful and birds harmful
Herman, Ottó & Owen, J. A. (Jean Allan)
833 Gutenberg downloadsen2016Difficulty 56 (Graduate)
Homo-Culture; Or, The Improvement of Offspring Through Wiser Generation
Holbrook, M. L. (Martin Luther)
833 Gutenberg downloadsen2010Difficulty 66 (Academic)
The Chain of Life in Geological Time A Sketch of the Origin and Succession of Animals and Plants
Dawson, John William, Sir
833 Gutenberg downloadsen2011Difficulty 56 (Graduate)
Field, Forest and Farm Things interesting to young nature-lovers, including some matters of moment to gardeners and fruit-growers
Fabre, Jean-Henri
832 Gutenberg downloadsen2022Difficulty 54 (Graduate)
Half hours with the lower animals : $b protozoans, sponges, corals, shells, insects, and crustaceans
Holder, Charles Frederick
832 Gutenberg downloadsen2016Difficulty 51 (Graduate)
Louis Pasteur: His Life and Labours
Vallery-Radot, René
832 Gutenberg downloadsen2014Difficulty 59 (Graduate)
The Chautauquan, Vol. 04, October 1883
Chautauqua Literary and Scientific Circle & Chautauqua Institution
831 Gutenberg downloadsen2016Difficulty 50 (College)
On Snake-Poison: Its Action and Its Antidote
Mueller, A.
830 Gutenberg downloadsen2010Difficulty 69 (Academic)
Scientific American, Volume XXXVI., No. 8, February 24, 1877 A Weekly Journal of Practical Information, Art, Science, Mechanics, Chemistry, and Manufactures.
Various
829 Gutenberg downloadsen2006Difficulty 54 (Graduate)
The Science and Philosophy of the Organism
Driesch, Hans
829 Gutenberg downloadsen2013Difficulty 67 (Academic)
De Canibus Britannicis: Of Englishe Dogges
Caius, John
828 Gutenberg downloadsen2008Difficulty 81 (Specialist)
Venoms: Venomous Animals and Antivenomous Serum-therapeutics
Calmette, A. (Albert)
828 Gutenberg downloadsen2016Difficulty 56 (Graduate)
An introduction to the study of fishes
Günther, Albert C. L. G. (Albert Carl Ludwig Gotthilf)
827 Gutenberg downloadsen2023Difficulty 74 (Expert)
William Harvey and the Discovery of the Circulation of the Blood
Huxley, Thomas Henry
827 Gutenberg downloadsen2001Difficulty 62 (Academic)
A History of Science — Volume 5
Williams, Henry Smith & Williams, Edward Huntington
826 Gutenberg downloadsen2009Difficulty 57 (Graduate)
Mimicry in Butterflies
Punnett, Reginald Crundall
825 Gutenberg downloadsen2013Difficulty 62 (Academic)
Life and Letters of Thomas Henry Huxley — Volume 1
Huxley, Thomas Henry
824 Gutenberg downloadsen2004Difficulty 58 (Graduate)
The Plants of Michigan Simple Keys for the Identification of the Native Seed Plants of the State
Gleason, Henry A. (Henry Allan)
824 Gutenberg downloadsen2010Difficulty 45 (College)
The Genetic Effects of Radiation
Asimov, Isaac & Dobzhansky, Theodosius
822 Gutenberg downloadsen2017Difficulty 59 (Graduate)
An Australian Bird Book: A Pocket Book for Field Use
Leach, John Albert
821 Gutenberg downloadsen2010Difficulty 51 (Graduate)
Stories of the Universe: Animal Life
Lindsay, B.
821 Gutenberg downloadsen2012Difficulty 51 (Graduate)
Butterflies Worth Knowing
Weed, Clarence Moores
819 Gutenberg downloadsen2011Difficulty 66 (Academic)
The Dog
Youatt, William
818 Gutenberg downloadsen2005Difficulty 60 (Graduate)
Wild Flowers An Aid to Knowledge of Our Wild Flowers and Their Insect Visitors
Blanchan, Neltje
818 Gutenberg downloadsen2002Difficulty 58 (Graduate)
General Anatomy, Applied to Physiology and Medicine, Vol. 1 (of 3)
Bichat, Xavier
817 Gutenberg downloadsen2017Difficulty 67 (Academic)
Elements of Structural and Systematic Botany For High Schools and Elementary College Courses
Campbell, Douglas Houghton
815 Gutenberg downloadsen2007Difficulty 57 (Graduate)
Journals of Travels in Assam, Burma, Bhootan, Afghanistan and the Neighbouring Countries
Griffith, William
815 Gutenberg downloadsen2005Difficulty 54 (Graduate)
Physiological Researches on Life and Death
Bichat, Xavier
815 Gutenberg downloadsen2018Difficulty 60 (Graduate)
Response in the Living and Non-Living
Bose, Jagadis Chandra
813 Gutenberg downloadsen2006Difficulty 65 (Academic)
A Historical Account of Useful Inventions and Scientific Discoveries Being a manual of instruction and entertainment.
Grant, George
812 Gutenberg downloadsen2016Difficulty 62 (Academic)
Garden Pests in New Zealand A Popular Manual for Practical Gardeners, Farmers and Schools
Miller, David
812 Gutenberg downloadsen2014Difficulty 71 (Expert)
Woman and Womanhood: A Search for Principles
Saleeby, C. W. (Caleb Williams)
812 Gutenberg downloadsen2006Difficulty 59 (Graduate)
Wood and Forest
Noyes, William
812 Gutenberg downloadsen2011Difficulty 51 (Graduate)
Significant Achievements in Space Bioscience 1958-1964
United States. National Aeronautics and Space Administration
810 Gutenberg downloadsen2012Difficulty 76 (Expert)
The Fantastic Clan: The Cactus Family
Thornber, J. J. (John James) & Bonker, Frances
810 Gutenberg downloadsen2014Difficulty 67 (Academic)
The heart of Africa, Vol. 1 (of 2)
Schweinfurth, Georg August
810 Gutenberg downloadsen2023Difficulty 81 (Specialist)
Directions for Collecting and Preserving Insects
Riley, Charles V. (Charles Valentine)
808 Gutenberg downloadsen2012Difficulty 70 (Academic)
Life and Matter: A Criticism of Professor Haeckel's "Riddle of the Universe"
Lodge, Oliver, Sir
808 Gutenberg downloadsen2008Difficulty 75 (Expert)
Unconscious Memory
Butler, Samuel
808 Gutenberg downloadsen2004Difficulty 64 (Academic)
Grasses : $b A handbook for use in the field and laboratory
Ward, H. Marshall (Harry Marshall)
807 Gutenberg downloadsen2015Difficulty 56 (Graduate)
Handbook of the Trees of New England
Dame, Lorin Low & Brooks, Henry M. (Henry Mason)
807 Gutenberg downloadsen2007Difficulty 53 (Graduate)
Prehistoric man
Duckworth, W. L. H. (Wynfrid Laurence Henry)
807 Gutenberg downloadsen2013Difficulty 57 (Graduate)
Alfred Russel Wallace: Letters and Reminiscences, Vol. 1
Wallace, Alfred Russel & Marchant, James, Sir
805 Gutenberg downloadsen2005Difficulty 65 (Academic)
Cave Hunting Researches on the evidence of caves respecting the early inhabitants of Europe
Dawkins, William Boyd
805 Gutenberg downloadsen2016Difficulty 77 (Expert)
The Science of Animal Locomotion (Zoopraxography) An Electro-Photographic Investigation of Consecutive Phases of Animal Movements
Muybridge, Eadweard
805 Gutenberg downloadsen2012Difficulty 64 (Academic)
A History of Science — Volume 2
Williams, Henry Smith & Williams, Edward Huntington
804 Gutenberg downloadsen1999Difficulty 63 (Academic)
Scientific American Supplement, No. 520, December 19, 1885
Various
804 Gutenberg downloadsen2004Difficulty 56 (Graduate)
Useful Knowledge: Volume 2. Vegetables Or, a familiar account of the various productions of nature
Bingley, William
804 Gutenberg downloadsen2018Difficulty 51 (Graduate)
Metapsychical phenomena : $b methods and observations
Maxwell, J. (Joseph)
802 Gutenberg downloadsen2014Difficulty 60 (Graduate)
Jelly-Fish, Star-Fish, and Sea-Urchins: Being a Research on Primitive Nervous Systems
Romanes, George John
801 Gutenberg downloadsen2014Difficulty 64 (Academic)
Bramble-Bees and Others
Fabre, Jean-Henri
799 Gutenberg downloadsen2002Difficulty 52 (Graduate)
Freshwater Sponges, Hydroids & Polyzoa
Annandale, Nelson
799 Gutenberg downloadsen2011Difficulty 61 (Academic)
Aphorisms and Reflections from the Works of T. H. Huxley
Huxley, Thomas Henry
795 Gutenberg downloadsen2011Difficulty 60 (Graduate)
Time and Change
Burroughs, John
795 Gutenberg downloadsen2004Difficulty 54 (Graduate)
Histology of medicinal plants
Mansfield, William James
793 Gutenberg downloadsen2021Difficulty 70 (Academic)
A history of land mammals in the western hemisphere
Scott, William Berryman
792 Gutenberg downloadsen2025Difficulty 66 (Academic)
Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, II. Band Von Galilei bis zur Mitte des XVIII. Jahrhunderts
Dannemann, Friedrich
792 Gutenberg downloadsde2017
Memoirs of the Distinguished Men of Science of Great Britain Living in the Years 1807-8
Walker, William
792 Gutenberg downloadsen2018Difficulty 61 (Academic)
Physics and Politics, or, Thoughts on the application of the principles of "natural selection" and "inheritance" to political society
Bagehot, Walter
792 Gutenberg downloadsen2003Difficulty 64 (Academic)
Seaside Studies in Natural History. Marine Animals of Massachusetts Bay. Radiates.
Agassiz, Elizabeth Cabot Cary & Agassiz, Alexander
792 Gutenberg downloadsen2011Difficulty 52 (Graduate)
The Breeding Birds of Kansas
Johnston, Richard F.
792 Gutenberg downloadsen2011Difficulty 74 (Expert)
The Origin of Vertebrates
Gaskell, Walter Holbrook
791 Gutenberg downloadsen2013Difficulty 82 (Specialist)
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
790 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Secrets of Earth and Sea
Lankester, E. Ray (Edwin Ray), Sir
790 Gutenberg downloadsen2016Difficulty 53 (Graduate)
A handbook of some South Indian grasses
Rangachari, K. & Tadulinga Mudaliyar, C.
788 Gutenberg downloadsen2007Difficulty 50 (College)
Text book of veterinary medicine, Volume 3 (of 5)
Law, James
788 Gutenberg downloadsen2023Difficulty 63 (Academic)
The Amphibians and Reptiles of Michoacán, México
Duellman, William Edward
788 Gutenberg downloadsen2010Difficulty 63 (Academic)
The Butterflies of the British Isles
South, Richard
788 Gutenberg downloadsen2013Difficulty 57 (Graduate)
The Mechanism of Life
Leduc, Stéphane
788 Gutenberg downloadsen2010Difficulty 63 (Academic)
The Industries of Animals
Houssay, Frédéric
787 Gutenberg downloadsen2009Difficulty 64 (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
785 Gutenberg downloadsen2013Difficulty 57 (Graduate)
Popular Books on Natural Science For Practical Use in Every Household, for Readers of All Classes
Bernstein, Aaron David
785 Gutenberg downloadsen2011Difficulty 50 (College)
Studies in the Theory of Descent, Volume I
Weismann, August
785 Gutenberg downloadsen2015Difficulty 68 (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
784 Gutenberg downloadsen2014Difficulty 56 (Graduate)
The Elements of Agriculture A Book for Young Farmers, with Questions Prepared for the Use of Schools
Waring, George E. (George Edwin)
784 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Appletons' Popular Science Monthly, March 1899 Volume LIV, No. 5, March 1899
Various
782 Gutenberg downloadsen2013Difficulty 57 (Graduate)
Harvey's Views on the Use of the Circulation of the Blood
Curtis, John Green
782 Gutenberg downloadsen2014Difficulty 69 (Academic)
Anthropoid apes
Hartmann, Robert
781 Gutenberg downloadsen2025Difficulty 53 (Graduate)
The Natural History of Cage Birds Their Management, Habits, Food, Diseases, Treatment, Breeding, and the Methods of Catching Them.
Bechstein, Johann Matthäus
780 Gutenberg downloadsen2012Difficulty 56 (Graduate)
Through Magic Glasses and Other Lectures A Sequel to The Fairyland of Science
Buckley, Arabella B. (Arabella Burton)
780 Gutenberg downloadsen2011Difficulty 58 (Graduate)
Subspeciation in the Kangaroo Rat, Dipodomys ordii KU. Vol 1 No 23
Setzer, Henry W.
779 Gutenberg downloadsen2013Difficulty 66 (Academic)
The Life of the Scorpion
Fabre, Jean-Henri
778 Gutenberg downloadsen2021Difficulty 49 (College)
Evolution: Its nature, its evidence, and its relation to religious thought
LeConte, Joseph
776 Gutenberg downloadsen2014Difficulty 88 (Specialist)
The Farmer's Veterinarian: A Practical Treatise on the Diseases of Farm Stock
Burkett, Charles William
776 Gutenberg downloadsen2017Difficulty 49 (College)
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
774 Gutenberg downloadsen2016Difficulty 77 (Expert)
Bees
Phillips, Everett Franklin
773 Gutenberg downloadsen2015Difficulty 52 (Graduate)
Metabolic Adaptation to Climate and Distribution of the Raccoon Procyon Lotor and Other Procyonidae
Mugaas, John N. & Mahlke-Johnson, Kathleen P. & Seidensticker, John
773 Gutenberg downloadsen2011Difficulty 74 (Expert)
Ecological Studies of the Timber Wolf in Northeastern Minnesota
Mech, L. David & Frenzel, Louis Daniel & Karns, P. D. & Ream, Robert R. & Winship, John W.
772 Gutenberg downloadsen2011Difficulty 52 (Graduate)
Essays on the Microscope Containing a Practical Description of the Most Improved Microscopes, a General History of Insects, etc., etc.
Adams, George
772 Gutenberg downloadsen2020Difficulty 62 (Academic)
Scientific American Supplement, No. 598, June 18, 1887
Various
772 Gutenberg downloadsen2004Difficulty 50 (College)
The Nests and Eggs of Indian Birds, Volume 1
Hume, Allan Octavian
772 Gutenberg downloadsen2004Difficulty 49 (College)
Gorillas & Chimpanzees
Garner, R. L. (Richard Lynch)
770 Gutenberg downloadsen2013Difficulty 51 (Graduate)
Species Plantarum, Sections IV-V
Linné, Carl von
770 Gutenberg downloadsla2008
Appletons' Popular Science Monthly, November 1898 Volume 54, November 1898
Various
769 Gutenberg downloadsen2013Difficulty 60 (Graduate)
The Fairy-Land of Science
Buckley, Arabella B. (Arabella Burton)
769 Gutenberg downloadsen2004Difficulty 48 (College)
Wild Animals of North America Intimate Studies of Big and Little Creatures of the Mammal Kingdom
Nelson, Edward William
768 Gutenberg downloadsen2019Difficulty 52 (Graduate)
Speciation and Evolution of the Pygmy Mice, Genus Baiomys
Packard, Robert L. (Robert Lewis)
767 Gutenberg downloadsen2011Difficulty 64 (Academic)
Species and Varieties, Their Origin by Mutation
Vries, Hugo de
767 Gutenberg downloadsen2005Difficulty 60 (Graduate)
The Popular Science Monthly, June, 1900 Vol. 57, May, 1900 to October, 1900
Various
767 Gutenberg downloadsen2014Difficulty 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
765 Gutenberg downloadsen2014Difficulty 60 (Graduate)
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)
765 Gutenberg downloadsen2012Difficulty 60 (Graduate)
The useful trees of northern Nigeria
Lely, Hugh Vandervaes
765 Gutenberg downloadsen2023Difficulty 56 (Graduate)
Cavity-Nesting Birds of North American Forests Agriculture Handbook 511
Scott, Virgil E. & Evans, Keith E. & Patton, David R. & Stone, Charles P.
764 Gutenberg downloadsen2015Difficulty 64 (Academic)
Journal of a tour in Marocco and the Great Atlas
Hooker, Joseph Dalton & Ball, John
764 Gutenberg downloadsen2023Difficulty 66 (Academic)
Speciation in the Brazilian Spiny Rats
Moojen, João
763 Gutenberg downloadsen2013Difficulty 70 (Academic)
British birds
Hudson, W. H. (William Henry) & Beddard, Frank E. (Frank Evers)
762 Gutenberg downloadsen2024Difficulty 67 (Academic)
Darwiniana : Essays — Volume 02
Huxley, Thomas Henry
762 Gutenberg downloadsen2004Difficulty 68 (Academic)
De Reis om de Wereld
Darwin, Charles
762 Gutenberg downloadsnl2010
On the Method of Zadig Essay #1 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
761 Gutenberg downloadsen2001Difficulty 66 (Academic)
The alligator and its allies
Reese, A. M. (Albert Moore)
761 Gutenberg downloadsen2023Difficulty 53 (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)
761 Gutenberg downloadsen2005Difficulty 58 (Graduate)
Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, III. Band Das Emporblühen der modernen Naturwissenschaften bis zur Entdeckung des Energieprinzipes
Dannemann, Friedrich
759 Gutenberg downloadsde2018
Little Masterpieces of Science: The Naturalist as Interpreter and Seer
Unknown
759 Gutenberg downloadsen2009Difficulty 63 (Academic)
Speciation of the Wandering Shrew
Findley, James S. (James Smith)
759 Gutenberg downloadsen2011Difficulty 62 (Academic)
The Life and Love of the Insect
Fabre, Jean-Henri
759 Gutenberg downloadsen2022Difficulty 50 (College)
Pioneers of Evolution from Thales to Huxley With an Intermediate Chapter on the Causes of Arrest of the Movement
Clodd, Edward
758 Gutenberg downloadsen2012Difficulty 58 (Graduate)
The Popular Science Monthly, September, 1900 Vol. 57, May, 1900 to October, 1900
Various
758 Gutenberg downloadsen2014Difficulty 77 (Expert)
The Origin of Species From 'The Westminster Review', April 1860
Huxley, Thomas Henry
757 Gutenberg downloadsen2001Difficulty 74 (Expert)
Trees: A Woodland Notebook Containing Observations on Certain British and Exotic Trees
Maxwell, Herbert, Sir
757 Gutenberg downloadsen2012Difficulty 59 (Graduate)
Life History and Ecology of the Five-Lined Skink, Eumeces fasciatus
Fitch, Henry S. (Henry Sheldon)
756 Gutenberg downloadsen2012Difficulty 62 (Academic)
A Population Study of the Prairie Vole (Microtus ochrogaster) in Northeastern Kansas
Martin, Edwin Perry
755 Gutenberg downloadsen2012Difficulty 61 (Academic)
Facts and Arguments for Darwin
Müller, Fritz
754 Gutenberg downloadsen2004Difficulty 70 (Academic)
The Making of Species
Dewar, Douglas & Finn, Frank
753 Gutenberg downloadsen2013Difficulty 72 (Expert)
Life History of the Kangaroo Rat
Vorhies, Charles Taylor & Taylor, Walter P. (Walter Penn)
752 Gutenberg downloadsen2006Difficulty 62 (Academic)
A century of science in America : $b with special reference to the American Journal of Science, 1818-1918
Unknown
750 Gutenberg downloadsen2024Difficulty 60 (Graduate)
Buffon's Natural History. Volume 07 (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
750 Gutenberg downloadsen2014Difficulty 60 (Graduate)
The Recent Mammals of Tamaulipas, México
Alvarez, Ticul
750 Gutenberg downloadsen2012Difficulty 56 (Graduate)
The Story of Evolution
McCabe, Joseph
750 Gutenberg downloadsen1997Difficulty 56 (Graduate)
Charles Darwin
Allen, Grant
749 Gutenberg downloadsen2010Difficulty 73 (Expert)
Domesticated animals : $b Their relation to man and to his advancement in civilization
Shaler, Nathaniel Southgate
748 Gutenberg downloadsen2008Difficulty 63 (Academic)
On the Seashore Cassell's "Eyes and No Eyes" Series, Book VII
Smith, R. Cadwallader
748 Gutenberg downloadsen2003Difficulty 35 (High School)
Louis Agassiz: His Life and Correspondence
Agassiz, Louis
747 Gutenberg downloadsen2004Difficulty 49 (College)
Mammals of the Southwest Mountains and Mesas
Olin, George
747 Gutenberg downloadsen2016Difficulty 57 (Graduate)
The Bird Study Book
Pearson, T. Gilbert (Thomas Gilbert)
747 Gutenberg downloadsen2007Difficulty 52 (Graduate)
The works of Francis Maitland Balfour, Volume 4 (of 4) : $b Plates
Balfour, Francis M. (Francis Maitland)
747 Gutenberg downloadsen2014Difficulty 50 (College)
History of Botany (1530-1860)
Sachs, Julius
746 Gutenberg downloadsen2020Difficulty 72 (Expert)
The Appendages, Anatomy, and Relationships of Trilobites
Raymond, Percy E. (Percy Edward)
746 Gutenberg downloadsen2012Difficulty 67 (Academic)
Eleanor Ormerod, LL. D., Economic Entomologist : Autobiography and Correspondence
Ormerod, Eleanor A. (Eleanor Anne)
745 Gutenberg downloadsen2020Difficulty 76 (Expert)
Hints towards the formation of a more comprehensive theory of life.
Coleridge, Samuel Taylor
745 Gutenberg downloadsen2008Difficulty 68 (Academic)
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
743 Gutenberg downloadsen2013Difficulty 48 (College)
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
742 Gutenberg downloadsen2023Difficulty 65 (Academic)
A Quantitative Study of the Nocturnal Migration of Birds
Lowery, George H., Jr.
740 Gutenberg downloadsen2011Difficulty 55 (Graduate)
Radioisotopes and Life Processes (Revised)
Kisieleski, Walter E. & Baserga, Renato
740 Gutenberg downloadsen2015Difficulty 66 (Academic)
A Guide for the Study of Animals
Whitney, Worrallo & Lucas, Frederic Colby & Shinn, Harold Brough & Smallwood, Mabel Elizabeth
739 Gutenberg downloadsen2011Difficulty 48 (College)
Appletons' Popular Science Monthly, February 1899 Volume LIV, No. 4, February 1899
Various
739 Gutenberg downloadsen2013Difficulty 57 (Graduate)
The Botanical Magazine, Vol. 06 Or, Flower-Garden Displayed
Curtis, William
739 Gutenberg downloadsen2007Difficulty 59 (Graduate)
An Elementary Text-book of the Microscope including a description of the methods of preparing and mounting objects, etc.
Griffith, J. W. (John William)
738 Gutenberg downloadsen2015Difficulty 52 (Graduate)
Appletons' Popular Science Monthly, January 1899 Volume LIV, No. 3, January 1899
Various
738 Gutenberg downloadsen2013Difficulty 56 (Graduate)
Les abeilles
Pérez, Jean M.
738 Gutenberg downloadsfr2011
Science and Morals and Other Essays
Windle, Bertram Coghill Alan, Sir
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The book of antelopes, vol. 1 (of 4)
Sclater, Philip Lutley & Thomas, Oldfield
738 Gutenberg downloadsen2023Difficulty 49 (College)
Flowers of the Southwest Deserts
Dodge, Natt N. (Natt Noyes)
737 Gutenberg downloadsen2016Difficulty 61 (Academic)
Ants and Some Other Insects: An Inquiry Into the Psychic Powers of These Animals
Forel, Auguste
736 Gutenberg downloadsen2016Difficulty 70 (Academic)
Zoological Illustrations, Second Series, Volume 3 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
736 Gutenberg downloadsen2013Difficulty 61 (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
735 Gutenberg downloadsen2014Difficulty 68 (Academic)
Darwin
Bradford, Gamaliel
734 Gutenberg downloadsen2023Difficulty 60 (Graduate)
The Last Link: Our Present Knowledge of the Descent of Man
Haeckel, Ernst
734 Gutenberg downloadsen2013Difficulty 63 (Academic)
Lectures and Essays
Huxley, Thomas Henry
733 Gutenberg downloadsen2004Difficulty 63 (Academic)
The Breath of Life
Burroughs, John
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Glimpses of Ocean Life; Or, Rock-Pools and the Lessons they Teach
Harper, John
732 Gutenberg downloadsen2016Difficulty 66 (Academic)
The Botanical Magazine, Vol. 01 Or, Flower-Garden Displayed
Curtis, William
732 Gutenberg downloadsen2005Difficulty 57 (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
731 Gutenberg downloadsen2014Difficulty 76 (Expert)
Illustrations of Exotic Entomology, Volume 2
Drury, Dru
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Cassell's book of birds; vol. 4
Brehm, Alfred Edmund
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Life and Letters of Thomas Henry Huxley — Volume 3
Huxley, Thomas Henry
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Ornithological biography, Vol. 4 (of 5) : $b An account of the habits of the birds of the United States of America
Audubon, John James
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Pearls & Parasites
Shipley, A. E. (Arthur Everett), Sir
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The Life-Story of Insects
Carpenter, George H. (George Herbert)
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A Critique of the Theory of Evolution
Morgan, Thomas Hunt
728 Gutenberg downloadsen2009Difficulty 57 (Graduate)
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
728 Gutenberg downloadsen2025Difficulty 65 (Academic)
Educação nova: As bases
Alves dos Santos, Augusto Joaquim
728 Gutenberg downloadspt2012
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
728 Gutenberg downloadsen2004Difficulty 42 (College)
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.
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Natural History of the Prairie Vole (Mammalian Genus Microtus) [KU. Vol. 1 No. 7]
Jameson, E. W. (Everett Williams)
727 Gutenberg downloadsen2011Difficulty 52 (Graduate)
Physiology
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The Essentials of Illustration A Practical Guide to the Reproduction of Drawings & Photographs for the Use of Scientists & Others
Hill, Thomas George
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Animal Parasites and Messmates
Beneden, P. J. van (Pierre Joseph)
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Barium: A Cause of the Loco-Weed Disease
Crawford, Albert C. (Albert Cornelius)
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The Illustrated Self-Instructor in Phrenology and Physiology
Fowler, O. S. (Orson Squire) & Fowler, L. N. (Lorenzo Niles)
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Histology of the Blood, Normal and Pathological
Ehrlich, Paul & Lazarus, Adolf
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The Taleef Shereef; Or, Indian Materia Medica
Unknown
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Lameness of the Horse Veterinary Practitioners' Series, No. 1
Lacroix, John Victor
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Natural History of the Racer Coluber constrictor
Fitch, Henry S. (Henry Sheldon)
723 Gutenberg downloadsen2013Difficulty 69 (Academic)
Natural Philosophy
Ostwald, Wilhelm
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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)
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The Biological Problem of To-day: Preformation Or Epigenesis? The Basis of a Theory of Organic Development
Hertwig, Oscar
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The Principles of Biology, Volume 2 (of 2)
Spencer, Herbert
723 Gutenberg downloadsen2022Difficulty 63 (Academic)
The Dinosaur Quarry. Dinosaur National Monument, Colorado-Utah
Good, John M. (John Maxwell) & Stucker, Gilbert F. & White, Theodore Elmer
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The life of Jean Henri Fabre, the entomologist, 1823-1910
Fabre, Augustin
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The Physical Basis of Mind Being the Second Series of Problems of Life and Mind.
Lewes, George Henry
722 Gutenberg downloadsen2019Difficulty 70 (Academic)
The Edinburgh New Philosophical Journal, Vol. XLIX April-October 1850
Various
721 Gutenberg downloadsen2013Difficulty 66 (Academic)
A Review of the Middle American Tree Frogs of the Genus Ptychohyla
Duellman, William Edward
720 Gutenberg downloadsen2011Difficulty 58 (Graduate)
Flowers of mountain and plain
Clements, Edith S. (Edith Schwartz)
719 Gutenberg downloadsen2014Difficulty 50 (College)
Animal Life and Intelligence
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718 Gutenberg downloadsen2015Difficulty 57 (Graduate)
The Dolphin in History
Montagu, Ashley & Lilly, John Cunningham
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Within the Deep Cassell's "Eyes and No Eyes" Series, Book VIII.
Smith, R. Cadwallader
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A Synopsis of the North American Lagomorpha
Hall, E. Raymond (Eugene Raymond)
716 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Beginners' botany
Bailey, L. H. (Liberty Hyde)
714 Gutenberg downloadsen2024Difficulty 50 (College)
Observations of a Naturalist in the Pacific Between 1896 and 1899, Volume 2 Plant-Dispersal
Guppy, H. B. (Henry Brougham)
714 Gutenberg downloadsen2017Difficulty 59 (Graduate)
Territory in Bird Life
Howard, Henry Eliot
714 Gutenberg downloadsen2010Difficulty 62 (Academic)
The Vivisectors' Directory Being a list of the licensed vivisectors in the United Kingdom, together with the leading physiologists in foreign laboratories
Unknown
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Britton, Thomas Allen
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Alfred Russel Wallace: Letters and Reminiscences, Vol. 2
Wallace, Alfred Russel & Marchant, James, Sir
713 Gutenberg downloadsen2005Difficulty 69 (Academic)
Neotropical Hylid Frogs, Genus Smilisca
Duellman, William Edward & Trueb, Linda
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Bacteria Especially as they are related to the economy of nature, to industrial processes, and to the public health
Newman, George, Sir
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Dragons of the Air: An Account of Extinct Flying Reptiles
Seeley, H. G. (Harry Govier)
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Evolution and Classification of the Pocket Gophers of the Subfamily Geomyinae
Russell, Robert J.
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Fishes of Chautauqua, Cowley and Elk Counties, Kansas
Metcalf, Artie L.
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The Study of Plant Life
Stopes, Marie Carmichael
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Life of Charles Darwin
Bettany, G. T. (George Thomas)
710 Gutenberg downloadsen2009Difficulty 63 (Academic)
Biology and Its Makers With Portraits and Other Illustrations
Locy, William A. (William Albert)
709 Gutenberg downloadsen2019Difficulty 56 (Graduate)
Darwinism and Race Progress
Haycraft, John Berry
709 Gutenberg downloadsen2014Difficulty 71 (Expert)
The Variation of Animals and Plants under Domestication — Volume 2
Darwin, Charles
709 Gutenberg downloadsen2001Difficulty 72 (Expert)
Common objects of the microscope
Wood, J. G. (John George)
708 Gutenberg downloadsen2017Difficulty 69 (Academic)
Zoological Illustrations, Second Series, Volume 2 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
708 Gutenberg downloadsen2013Difficulty 60 (Graduate)
Plants Poisonous to Live Stock
Long, Harold Cecil
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The Botanical Magazine, Vol. 07 Or, Flower-Garden Displayed
Curtis, William
707 Gutenberg downloadsen2007Difficulty 58 (Graduate)
An Account of the Insects Noxious to Agriculture and Plants in New Zealand The Scale Insects (Coccididae)
Maskell, William Miles
704 Gutenberg downloadsen2015Difficulty 53 (Graduate)
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
702 Gutenberg downloadsen2023Difficulty 60 (Graduate)
The Geological History of Plants
Dawson, John William, Sir
702 Gutenberg downloadsen2016Difficulty 55 (Graduate)
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
701 Gutenberg downloadsen2014Difficulty 61 (Academic)
On Some Fossil Remains of Man
Huxley, Thomas Henry
701 Gutenberg downloadsen2001Difficulty 60 (Graduate)
On the Relations of Man to the Lower Animals
Huxley, Thomas Henry
700 Gutenberg downloadsen2001Difficulty 72 (Expert)
Birds, Illustrated by Color Photography, Vol. 1, No. 6 June, 1897
Various
699 Gutenberg downloadsen2009Difficulty 48 (College)
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
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The British Woodlice Being a Monograph of the Terrestrial Isopod Crustacea Occurring in the British Islands
Webb, Wilfred Mark & Sillem, Charles
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The Forests of Mount Rainier National Park
Allen, G. F. (Grenville F.)
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Marvels of Pond-life Or, A Year's Microscopic Recreations Among the Polyps, Infusoria, Rotifers, Water-bears and Polyzoa
Slack, Henry James
698 Gutenberg downloadsen2011Difficulty 74 (Expert)
Notes and Letters on the Natural History of Norfolk More Especially on the Birds and Fishes
Browne, Thomas, Sir
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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)
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Section Cutting and Staining A practical introduction to histological methods for students and practitioners
Colman, Walter S.
698 Gutenberg downloadsen2016Difficulty 50 (College)
Scientific American Supplement, No. 363, December 16, 1882
Various
697 Gutenberg downloadsen2005Difficulty 62 (Academic)
Appletons' Popular Science Monthly, May, 1900 Vol. 57, May, 1900 to October, 1900
Various
696 Gutenberg downloadsen2014Difficulty 60 (Graduate)
Cassell's book of birds; vol. 3
Brehm, Alfred Edmund
696 Gutenberg downloadsen2019Difficulty 62 (Academic)
Poisonous Dwellers of the Desert
Dodge, Natt N. (Natt Noyes)
696 Gutenberg downloadsen2017Difficulty 61 (Academic)
The Adductor Muscles of the Jaw In Some Primitive Reptiles
Fox, Richard C.
696 Gutenberg downloadsen2009Difficulty 66 (Academic)
The horse's mouth, showing the age by the teeth
Mayhew, Edward
696 Gutenberg downloadsen2014Difficulty 55 (Graduate)
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
696 Gutenberg downloadsen2011Difficulty 48 (College)
At the Deathbed of Darwinism: A Series of Papers
Dennert, Eberhard
695 Gutenberg downloadsen2007Difficulty 68 (Academic)
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
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Luck, or Cunning, as the Main Means of Organic Modification
Butler, Samuel
694 Gutenberg downloadsen2004Difficulty 61 (Academic)
Scientific American Supplement, No. 492, June 6, 1885
Various
694 Gutenberg downloadsen2004Difficulty 53 (Graduate)
Abstracts of Papers Read at the First International Eugenics Congress University of London, July, 1912
International Eugenics Congress (1st : 1912 : London)
693 Gutenberg downloadsen2014Difficulty 65 (Academic)
Dactylography; Or, The Study of Finger-prints
Faulds, Henry
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Lectures on Evolution Essay #3 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
693 Gutenberg downloadsen2001Difficulty 69 (Academic)
On the Reception of the 'Origin of Species'
Huxley, Thomas Henry
693 Gutenberg downloadsen2000Difficulty 66 (Academic)
Dissection of the Platana and the Frog
Gilchrist, J. D. F. (John Dow Fisher) & Bonde, Cecil von
692 Gutenberg downloadsen2015Difficulty 51 (Graduate)
Physiology: The Science of the Body
Martin, Ernest G.
692 Gutenberg downloadsen2015Difficulty 53 (Graduate)
Science in Arcady
Allen, Grant
692 Gutenberg downloadsen2005Difficulty 63 (Academic)
Journal of the Proceedings of the Linnean Society - Vol. 4 Zoology
Linnean Society of London
691 Gutenberg downloadsen2014Difficulty 61 (Academic)
Recuerdos de mi vida (tomo 2 de 2)
Ramón y Cajal, Santiago
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The Monist, Vol. 1, 1890-1891 : $b A quarterly magazine
Various
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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
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Zoological Illustrations, Second Series, Volume 1 or, Original Figures and Descriptions of New, Rare, or Interesting Animals
Swainson, William
690 Gutenberg downloadsen2013Difficulty 59 (Graduate)
Evolution of Life and Form Four lectures delivered at the twenty-third anniversary meeting of the Theosophical Society at Adyar, Madras, 1898
Besant, Annie
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Life and death
Dastre, A. (Albert)
689 Gutenberg downloadsen2021Difficulty 56 (Graduate)
Scientific American Supplement, No. 315, January 14, 1882
Various
689 Gutenberg downloadsen2006Difficulty 63 (Academic)
Scientific American, Vol. XXXIX.No. 6. [New Series.], August 10, 1878
Various
688 Gutenberg downloadsen2013Difficulty 54 (Graduate)
Grundriß der menschlichen Erblichkeitslehre und Rassenhygiene (1/2) Menschliche Erblichkeitslehre
Baur, Erwin & Fischer, Eugen & Lenz, Fritz
687 Gutenberg downloadsde2015
Last Words on Evolution: A Popular Retrospect and Summary
Haeckel, Ernst
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Species Plantarum, Sections XI-XIII
Linné, Carl von
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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)
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Inheritance of Characteristics in Domestic Fowl
Davenport, Charles Benedict
686 Gutenberg downloadsen2015Difficulty 50 (College)
Scientific American Supplement, No. 388, June 9, 1883
Various
686 Gutenberg downloadsen2005Difficulty 56 (Graduate)
The Life of an Insect being a history of the changes of insects from the egg to the perfect being.
Unknown
686 Gutenberg downloadsen2014Difficulty 62 (Academic)
British Butterflies: Figures and Descriptions of Every Native Species
Coleman, W. S. (William Stephen)
685 Gutenberg downloadsen2010Difficulty 65 (Academic)
Nouvel atlas de poche des champignons Comestibles et Vénéneux les plus répandus. Série II (Première édition)
Dumée, Paul
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Souvenirs entomologiques - Livre I Étude sur l'instinct et les moeurs des insectes
Fabre, Jean-Henri
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The Life of the Weevil
Fabre, Jean-Henri & Teixeira de Mattos, Alexander
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Little Masterpieces of Science: Health and Healing
Unknown
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Scientific American magazine Vol 2. No. 3 Oct 10 1846 The Advocate of Industry and Journal of Scientific, Mechanical and Other Improvements
Various
682 Gutenberg downloadsen2009Difficulty 49 (College)
The book of antelopes, vol. 3 (of 4)
Sclater, Philip Lutley & Thomas, Oldfield
682 Gutenberg downloadsen2023Difficulty 45 (College)
Chambers's Elementary Science Readers Book I
Various
681 Gutenberg downloadsen2006Difficulty 27 (Middle School)
Die Cellularpathologie in ihrer Begründung auf physiologische und pathologische Gewebelehre
Virchow, Rudolf
681 Gutenberg downloadsde2014
Disease in captive wild mammals and birds : $b incidence, description, comparison
Fox, Herbert
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Scientific American Supplement, No. 711, August 17, 1889
Various
681 Gutenberg downloadsen2005Difficulty 61 (Academic)
The Lights of the Church and the Light of Science Essay #6 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
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Das Mikroskop und seine Anwendung Ein Leitfaden bei mikroskopischen Untersuchungen
Hager, Hermann
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The Migration of Birds
Coward, T. A. (Thomas Alfred)
680 Gutenberg downloadsen2013Difficulty 67 (Academic)
Appletons' Popular Science Monthly, April 1899 Volume LIV, No. 6, April 1899
Various
679 Gutenberg downloadsen2013Difficulty 56 (Graduate)
Fathers of Biology
McRae, Charles
679 Gutenberg downloadsen2008Difficulty 64 (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
679 Gutenberg downloadsen2020Difficulty 73 (Expert)
The romance of insect life : $b Interesting descriptions of the strange and curious in the insect world
Selous, Edmund
679 Gutenberg downloadsen2023Difficulty 76 (Expert)
The Wild Elephant and the Method of Capturing and Taming it in Ceylon
Tennent, James Emerson, Sir
679 Gutenberg downloadsen2018Difficulty 65 (Academic)
Darwinism stated by Darwin himself Characteristic passages from the writings of Charles Darwin
Darwin, Charles
678 Gutenberg downloadsen2022Difficulty 64 (Academic)
The Botanical Magazine, Vol. 02 Or, Flower-Garden Displayed
Curtis, William
678 Gutenberg downloadsen2006Difficulty 57 (Graduate)
Mr. Gladstone and Genesis Essay #5 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
677 Gutenberg downloadsen2001Difficulty 59 (Graduate)
Problems of Genetics
Bateson, William
677 Gutenberg downloadsen2014Difficulty 65 (Academic)
Travels into North America, Volume 2 (of 3)
Kalm, Pehr
677 Gutenberg downloadsen2023Difficulty 47 (College)
Living lights : $b A popular account of phosphorescent animals and vegetables
Holder, Charles Frederick
676 Gutenberg downloadsen2025Difficulty 58 (Graduate)
Quadrupeds, What They Are and Where Found: A Book of Zoology for Boys
Reid, Mayne
674 Gutenberg downloadsen2007Difficulty 55 (Graduate)
North American Jumping Mice (Genus Zapus)
Krutzsch, Philip H. (Philip Henry)
672 Gutenberg downloadsen2012Difficulty 64 (Academic)
On the Advisableness of Improving Natural Knowledge
Huxley, Thomas Henry
672 Gutenberg downloadsen2001Difficulty 72 (Expert)
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
671 Gutenberg downloadsen2005Difficulty 64 (Academic)
Scientific American Supplement, No. 795, March 28, 1891
Various
671 Gutenberg downloadsen2004Difficulty 62 (Academic)
Careers in Atomic Energy
McIlhenny, Loyce J.
670 Gutenberg downloadsen2013Difficulty 68 (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
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Some Reptiles and Amphibians from Korea
Webb, Robert G. (Robert Gravem) & Byers, George William & Jones, J. Knox
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The Flea
Russell, Harold
670 Gutenberg downloadsen2014Difficulty 53 (Graduate)
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.
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The romance of the microscope : $b 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)
670 Gutenberg downloadsen2015Difficulty 55 (Graduate)
Evolution and creation
Hardwicke, Herbert Junius
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Scientific American Supplement, No. 433, April 19, 1884
Various
668 Gutenberg downloadsen2005Difficulty 66 (Academic)
Studies in Spermatogenesis (Part 1 of 2)
Stevens, N. M. (Nettie Maria)
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The ivory king : $b A popular history of the elephant and its allies
Holder, Charles Frederick
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Insect life: Souvenirs of a naturalist
Fabre, Jean-Henri
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Marine Protozoa from Woods Hole Bulletin of the United States Fish Commission 21:415-468, 1901
Calkins, Gary N. (Gary Nathan)
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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
666 Gutenberg downloadsen2012Difficulty 56 (Graduate)
On Germinal Selection as a Source of Definite Variation
Weismann, August
666 Gutenberg downloadsen2010Difficulty 69 (Academic)
Appletons' Popular Science Monthly, March 1900 Vol. 56, Nov. 1899 to April, 1900
Various
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Being Well-Born: An Introduction to Eugenics
Guyer, Michael F. (Michael Frederic)
665 Gutenberg downloadsen2012Difficulty 85 (Specialist)
Food Poisoning
Jordan, Edwin O. (Edwin Oakes)
665 Gutenberg downloadsen2010Difficulty 65 (Academic)
On the Variation of Species, with Especial Reference to the Insecta Followed by an Inquiry into the Nature of Genera
Wollaston, Thomas Vernon
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Gosse, Philip Henry
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The Principal Species of Wood: Their Characteristic Properties First Edition
Snow, Charles H. (Charles Henry)
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Warum wir sterben
Lipschütz, Alejandro
665 Gutenberg downloadsde2008
Earthworms and Their Allies
Beddard, Frank E. (Frank Evers)
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Geological Contemporaneity and Persistent Types of Life
Huxley, Thomas Henry
664 Gutenberg downloadsen2001Difficulty 72 (Expert)
Scientific American Supplement No. 822, October 3, 1891
Various
664 Gutenberg downloadsen2005Difficulty 55 (Graduate)
Synopsis of Some Genera of the Large Pyrenomycetes Camillea, Thamnomyces, Engleromyces
Lloyd, C. G. (Curtis Gates)
664 Gutenberg downloadsen2007Difficulty 52 (Graduate)
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Sutro, Emil
663 Gutenberg downloadsen2015Difficulty 63 (Academic)
More Beetles
Fabre, Jean-Henri
663 Gutenberg downloadsen2022Difficulty 47 (College)
Natur und Mensch Sechs Abschnitte aus Werken von Ernst Haeckel
Haeckel, Ernst
663 Gutenberg downloadsde2015
Scientific American Supplement, No. 299, September 24, 1881
Various
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The Glands Regulating Personality A Study of the Glands of Internal Secretion in Relation to the Types of Human Nature
Berman, Louis
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An ethical problem; or, Sidelights upon scientific experimentation on man and animals
Leffingwell, Albert
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On the Study of Zoology
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The Dancing Mouse: A Study in Animal Behavior
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A Check-List of the Birds of Idaho
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A Theory of Creation: A Review of 'Vestiges of the Natural History of Creation'
Bowen, Francis
660 Gutenberg downloadsen2008Difficulty 67 (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
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Die epiphytische Vegetation Amerikas
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Physiological economy in nutrition, with special reference to the minimal proteid requirement of the healthy man an experimental study
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Studies in the Theory of Descent, Volume II
Weismann, August
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The Pocket Gophers (Genus Thomomys) of Utah University of Kansas Publications, Museum of Natural History, Vol. 1 No. 1
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659 Gutenberg downloadsen2012Difficulty 57 (Graduate)
Vertebrates from the Barrier Island of Tamaulipas, México
Selander, Robert K. & Johnston, Richard F. & Raun, Gerald G. & Wilks, B. J.
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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
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Birds' Nests, Eggs and Egg-Collecting
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658 Gutenberg downloadsen2014Difficulty 65 (Academic)
Species Plantarum, Sections VI-X
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Outlines of Creation
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657 Gutenberg downloadsen2015Difficulty 68 (Academic)
Ideen zu einer Physiognomik der Gewächse
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Wasps, Social and Solitary
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A Revision of Snakes of the Genus Conophis (Family Colubridae, from Middle America)
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A Taxonomic Study of the Middle American Snake, Pituophis deppei
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New-England's rarities discovered : $b In birds, beasts, fishes, serpents, and plants of that country
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The Brain and the Voice in Speech and Song
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653 Gutenberg downloadsen2004Difficulty 68 (Academic)
The Evolutionist at Large
Allen, Grant
653 Gutenberg downloadsen2014Difficulty 55 (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
652 Gutenberg downloadsen2014Difficulty 61 (Academic)
British Pomology Or, the History, Description, Classification, and Synonymes, of the Fruits and Fruit Trees of Great Britain
Hogg, Robert
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The Birds of Australia, Vol. 1 of 7
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651 Gutenberg downloadsen2021Difficulty 45 (College)
Scientific American Supplement, No. 275, April 9, 1881
Various
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The Rise and Progress of Palaeontology Essay #2 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
650 Gutenberg downloadsen2001Difficulty 77 (Expert)
Beginners' zoology
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On the phenomena of hybridity in the genus Homo
Broca, Paul
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The Life and Letters of George John Romanes, M.A., LL.D., F.R.S.
Romanes, George John & Romanes, Ethel Duncan
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Carpet Beetles and Their Control
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648 Gutenberg downloadsen2019Difficulty 55 (Graduate)
Histoire des légumes
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Mammals of Northwestern South Dakota
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648 Gutenberg downloadsen2010Difficulty 50 (College)
Field Mice as Farm and Orchard Pests
Lantz, David E. (David Ernest)
647 Gutenberg downloadsen2013Difficulty 54 (Graduate)
The Interpreters of Genesis and the Interpreters of Nature Essay #4 from "Science and Hebrew Tradition"
Huxley, Thomas Henry
647 Gutenberg downloadsen2001Difficulty 65 (Academic)
The Tropical World Aspects of man and nature in the equatorial regions of the globe.
Hartwig, G. (Georg)
647 Gutenberg downloadsen2020Difficulty 95 (Quantum Electrodynamics)
Mendel's principles of heredity: A defence
Bateson, William & Mendel, Gregor
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The Story of Creation as Told By Theology and By Science
Ackland, T. S. (Thomas Suter)
644 Gutenberg downloadsen2003Difficulty 62 (Academic)
Beginselen der dierkunde
Ritzema Bos, J. (Jan)
643 Gutenberg downloadsnl2010
Theory of circulation by respiration : $b synopsis of its principles and history
Willard, Emma
643 Gutenberg downloadsen2006Difficulty 57 (Graduate)
Yeast
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643 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
642 Gutenberg downloadsen2004Difficulty 65 (Academic)
The Chautauquan, Vol. 05, April 1885
Chautauqua Literary and Scientific Circle & Chautauqua Institution
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How to Know the Ferns
Bastin, S. Leonard
641 Gutenberg downloadsen2014Difficulty 50 (College)
L'Afrique centrale française : $b Récit du voyage de la mission
Chevalier, Auguste & Mission Chari-Lac Tchad (1902-1904)
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Sertum Anglicum, seu, Plantae Rariores quae in Hortis Juxta Londinum Imprimis in Horto Regio Kewensi excoluntur, ab anno 1786 ad annum 1787 observata
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Colouration in Animals and Plants
Tylor, Alfred
639 Gutenberg downloadsen2014Difficulty 56 (Graduate)
The Academic Gregories
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639 Gutenberg downloadsen2016Difficulty 59 (Graduate)
A Distributional Study of the Amphibians of the Isthmus of Tehuantepec, México
Duellman, William Edward
638 Gutenberg downloadsen2011Difficulty 65 (Academic)
Bee Keeping
Benton, Frank
638 Gutenberg downloadsen2015Difficulty 63 (Academic)
Creation and Its Records A Brief Statement of Christian Belief with Reference to Modern Facts and Ancient Scripture
Baden-Powell, B. H. (Baden Henry)
638 Gutenberg downloadsen2004Difficulty 62 (Academic)
The Lobster Fishery of Maine Bulletin of the United States Fish Commission, Vol. 19, Pages 241-265, 1899
Cobb, John N. (John Nathan)
638 Gutenberg downloadsen2006Difficulty 51 (Graduate)
A New Doglike Carnivore, Genus Cynarctus, From the Clarendonian, Pliocene, of Texas
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
637 Gutenberg downloadsen2009Difficulty 53 (Graduate)
Rede, gehalten bei der Eröffnung der Versammlung deutscher Naturforscher und Ärzte in Berlin, am 18. September 1828
Humboldt, Alexander von
637 Gutenberg downloadsde2007
The Systematics of the Frogs of the Hyla Rubra Group in Middle America
León, Juan R.
637 Gutenberg downloadsen2010Difficulty 60 (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.
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Darwin, and After Darwin, Volume 3 of 3 Post-Darwinian Questions: Isolation and Physiological Selection
Romanes, George John
636 Gutenberg downloadsen2011Difficulty 66 (Academic)
Fishing Grounds of the Gulf of Maine
Rich, Walter H. (Walter Herbert)
636 Gutenberg downloadsen2005Difficulty 57 (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
636 Gutenberg downloadsen2021Difficulty 66 (Academic)
Middle American frogs of the Hyla microcephala group
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Venomous arthropod handbook : $b envenomization symptoms/treatment, identification, biology and control
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634 Gutenberg downloadsen2023Difficulty 58 (Graduate)
Grundriß der menschlichen Erblichkeitslehre und Rassenhygiene (2/2) Menschliche Auslese und Rassenhygiene
Lenz, Fritz
634 Gutenberg downloadsde2015
Le monde de la mer
Moquin-Tandon, Alfred
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The Ancestry of Modern Amphibia: A Review of the Evidence
Eaton, Theodore H. (Theodore Hildreth)
634 Gutenberg downloadsen2011Difficulty 69 (Academic)
The Chautauquan, Vol. 05, June 1885, No. 9
Chautauqua Literary and Scientific Circle & Chautauqua Institution
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Travels into North America, Volume 3 (of 3)
Kalm, Pehr
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Biology : $b A lecture delivered at Columbia University in the series on Science, Philosophy and Art November 20, 1907
Wilson, Edmund B. (Edmund Beecher)
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British Sea Birds
Dixon, Charles
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Les Phénomènes Psychiques Occultes: État Actuel de la Question
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Het Leven der Dieren. Deel 3. Afdeling 2. De Visschen
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Het Leven der Dieren. Derde Deel, Hoofdstuk 1 tot 4, De Kruipende Dieren
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The Botanical Magazine, Vol. 05 Or, Flower-Garden Displayed
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Amphibians and Reptiles of the Rainforests of Southern El Petén, Guatemala
Duellman, William Edward
630 Gutenberg downloadsen2011Difficulty 64 (Academic)
Catholic Churchmen in Science [First Series] Sketches of the Lives of Catholic Ecclesiastics Who Were Among the Great Founders in Science
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Mendelism Third Edition
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630 Gutenberg downloadsen2009Difficulty 61 (Academic)
Migration of Birds (1979)
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The Crayfish: An Introduction to the Study of Zoology.
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A Report upon the Mollusk Fisheries of Massachusetts
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Initiative in Evolution
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Plague Its Cause and the Manner of its Extension, Its Menace, Its Control and Suppression, Its Diagnosis and Treatment
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The Dwelling House
Poore, George Vivian
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The Hand Phrenologically Considered Being a Glimpse at the Relation of the Mind with the Organisation of the Body
Anonymous
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The physiology of digestion considered with relation to the principles of dietetics
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627 Gutenberg downloadsen2023Difficulty 83 (Specialist)
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Mammals of the San Gabriel Mountains of California
Vaughan, Terry A.
625 Gutenberg downloadsen2011Difficulty 63 (Academic)
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
624 Gutenberg downloadsen2018Difficulty 64 (Academic)
Animal Castration
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European Fungus Flora: Agaricaceae
Massee, George
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Atoms, Nature, and Man: Man-made Radioactivity in the Environment
Hines, Neal O.
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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)
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The Popular Science Monthly, August, 1900 Vol. 57, May, 1900 to October, 1900
Various
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Apes and Monkeys: Their Life and Language
Garner, R. L. (Richard Lynch)
622 Gutenberg downloadsen2022Difficulty 55 (Graduate)
Scientific American Supplement, No. 799, April 25, 1891
Various
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American Addresses, with a Lecture on the Study of Biology
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The Pecan and its Culture
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Thoughts on Religion
Romanes, George John
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House Rats and Mice
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620 Gutenberg downloadsen2011Difficulty 51 (Graduate)
Scientific American Supplement, No. 787, January 31, 1891
Various
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The Minor Horrors of War
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620 Gutenberg downloadsen2021Difficulty 51 (Graduate)
Was Man Created?
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620 Gutenberg downloadsen2009Difficulty 66 (Academic)
Geographic Range of the Hooded Skunk, Mephitis macroura With Description of a New Subspecies from Mexico
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
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Grundzüge der Paläontologie (Paläozoologie). 2. Abteilung: Vertebrata.
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Scientific American Supplement, No. 303, October 22, 1881
Various
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The Postnatal Development of Two Broods of Great Horned Owls (Bubo virginianus)
Hoffmeister, Donald Frederick & Setzer, Henry W.
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Aspects of Reproduction and Development in the Prairie Vole (Microtus ochrogaster)
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Buchanan's Journal of Man, August 1887 Volume 1, Number 7
Unknown
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Haeckel : $b his life and work
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Scientific American magazine, Vol. 2 Issue 1 The advocate of Industry and Journal of Scientific, Mechanical and Other Improvements
Various
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The Destiny of Man, Viewed in the Light of His Origin
Fiske, John
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Treatise on the Anatomy and Physiology of the Mucous Membranes With Illustrative Pathological Observations
Bichat, Xavier
617 Gutenberg downloadsen2016Difficulty 67 (Academic)
Evolution
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General Anatomy, Applied to Physiology and Medicine, Vol. 3 (of 3)
Bichat, Xavier
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Life Movements in Plants, Volume II
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Respiration Calorimeters for Studying the Respiratory Exchange and Energy Transformations of Man
Benedict, Francis Gano & Carpenter, Thorne M. (Thorne Martin)
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The book of antelopes, vol. 4 (of 4)
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The Evolution of Man — Volume 1
Haeckel, Ernst
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The zoology of the voyage of H.M.S. Beagle [vol. 3 of 5] : $b Birds
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A New Pocket Gopher (Genus Thomomys), from Eastern Colorado
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A Text-Book of Horseshoeing, for Horseshoers and Veterinarians
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The Behavior of the Honey Bee in Pollen Collecting
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A Mechanical Account of Poisons in Several Essays
Mead, Richard
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Beautiful Ferns
Eaton, Daniel Cady
611 Gutenberg downloadsen2014Difficulty 58 (Graduate)
Mammals of Mesa Verde National Park, Colorado
Anderson, Sydney
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The History of the European Fauna
Scharff, R. F. (Robert Francis)
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Zakflora voor Suriname [Deel I] Bulletin van het Koloniaal Museum te Haarlem No. 47.
Pulle, A. A. (August Adriaan)
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A Monograph of Odontoglossum
Bateman, Jas. (James)
610 Gutenberg downloadsen2014Difficulty 61 (Academic)
Ecological Observations on the Woodrat, Neotoma floridana
Fitch, Henry S. (Henry Sheldon) & Rainey, Dennis G.
610 Gutenberg downloadsen2010Difficulty 59 (Graduate)
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
608 Gutenberg downloadsen2001Difficulty 65 (Academic)
Geographic Variation in the Pocket Gopher, Cratogeomys castanops, in Coahuila, México
Russell, Robert J. & Baker, Rollin H. (Rollin Harold)
607 Gutenberg downloadsen2010Difficulty 64 (Academic)
The Myxomycetes of the Miami Valley, Ohio
Morgan, A. P. (Andrew Price)
607 Gutenberg downloadsen2009Difficulty 63 (Academic)
A Synopsis of Neotropical Hylid Frogs, Genus Osteocephalus
Trueb, Linda & Duellman, William Edward
606 Gutenberg downloadsen2011Difficulty 67 (Academic)
Ecology of the Opossum on a Natural Area in Northeastern Kansas
Fitch, Henry S. (Henry Sheldon) & Sandidge, Lewis L.
606 Gutenberg downloadsen2011Difficulty 62 (Academic)
Lives of Eminent Zoologists, from Aristotle to Linnæus with Introductory remarks on the Study of Natural History
MacGillivray, William
606 Gutenberg downloadsen2010Difficulty 84 (Specialist)
The Evolution of Man Scientifically Disproved in 50 Arguments
Williams, William A. (William Asbury)
605 Gutenberg downloadsen2005Difficulty 55 (Graduate)
The Toxicity of Caffein: An experimental study on different species of animals
Salant, William & Rieger, J. B. (John Benjamin)
605 Gutenberg downloadsen2014Difficulty 63 (Academic)
Illustrations of the Birds of California, Texas, Oregon, British and Russian America
Cassin, John
604 Gutenberg downloadsen2021Difficulty 63 (Academic)
L'Académie des sciences et les académiciens de 1666 à 1793
Bertrand, Joseph
604 Gutenberg downloadsfr2016
Scientific American Supplement, No. 648, June 2, 1888.
Various
604 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Essays in eugenics
Galton, Francis
603 Gutenberg downloadsen2024Difficulty 59 (Graduate)
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
603 Gutenberg downloadsen2022Difficulty 53 (Graduate)
A New Order of Fishlike Amphibia From the Pennsylvanian of Kansas
Eaton, Theodore H. (Theodore Hildreth) & Stewart, Peggy Lou
602 Gutenberg downloadsen2010Difficulty 55 (Graduate)
A New Subspecies of Lizard, Cnemidophorus sacki, from Michoacán, México
Duellman, William Edward
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Geographic Variation in the Pocket Gopher, Thomomys bottae, in Colorado
Youngman, Phillip M.
602 Gutenberg downloadsen2011Difficulty 57 (Graduate)
I funghi mangerecci e velenosi dell'Europa media con speciale riguardo a quelli che crescono nel Trentino - II edizione riveduta ed aumentata
Bresadola, Giacomo
602 Gutenberg downloadsit2013
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
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The Baculum in Microtine Rodents
Anderson, Sydney
602 Gutenberg downloadsen2011Difficulty 64 (Academic)
The Diatomaceæ of Philadelphia and Vicinity
Boyer, Charles S. (Charles Sumner)
602 Gutenberg downloadsen2014Difficulty 67 (Academic)
Scientific American Supplement, No. 794, March 21, 1891
Various
601 Gutenberg downloadsen2005Difficulty 52 (Graduate)
The honey-bee: its nature, homes and products
Harris, William Hetherington
601 Gutenberg downloadsen2022Difficulty 56 (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
601 Gutenberg downloadsen2001Difficulty 64 (Academic)
Catalogue of Economic Plants in the Collection of the U. S. Department of Agriculture
Saunders, William
600 Gutenberg downloadsen2008Difficulty 52 (Graduate)
New observations on the natural history of bees
Huber, François
600 Gutenberg downloadsen2008Difficulty 57 (Graduate)
The Popular Science Monthly, July, 1900 Vol. 57, May, 1900 to October, 1900
Various
600 Gutenberg downloadsen2014Difficulty 56 (Graduate)
A Field Study of the Kansas Ant-Eating Frog, Gastrophryne olivacea
Fitch, Henry S. (Henry Sheldon)
599 Gutenberg downloadsen2010Difficulty 55 (Graduate)
On the cattle plague: or, Contagious typhus in horned cattle. Its history, origin, description, and treatment
Bourguignon, Honoré
599 Gutenberg downloadsen2011Difficulty 69 (Academic)
Life histories of North American woodpeckers
Bent, Arthur Cleveland
598 Gutenberg downloadsen2024Difficulty 65 (Academic)
Scientific American Supplement, No. 385, May 19, 1883
Various
598 Gutenberg downloadsen2005Difficulty 58 (Graduate)
Aspects of nature, in different lands and different climates (Vol. 2 of 2) with scientific elucidations
Humboldt, Alexander von
597 Gutenberg downloadsen2022Difficulty 72 (Expert)
Desert and water gardens of the Red Sea : $b Being an account of the natives and the shore formations of the coast
Crossland, Cyril
597 Gutenberg downloadsen2023Difficulty 50 (College)
Life: Its True Genesis
Flaccus, Horatius
597 Gutenberg downloadsen2005Difficulty 60 (Graduate)
Criticisms on "The Origin of Species" From 'The Natural History Review', 1864
Huxley, Thomas Henry
596 Gutenberg downloadsen2001Difficulty 64 (Academic)
Memoir on the Dodo (Didus ineptus, Linn.)
Owen, Richard
596 Gutenberg downloadsen2025Difficulty 57 (Graduate)
Parasiten der Honigbiene und die durch dieselben bedingten Krankheiten dieses Insects.
Assmuss, Eduard Philibert
596 Gutenberg downloadsde2006
Scientific American Supplement, No. 286, June 25, 1881
Various
596 Gutenberg downloadsen2005Difficulty 53 (Graduate)
The octopus : $b or, The "devil-fish" of fiction and of fact
Lee, Henry
596 Gutenberg downloadsen2023Difficulty 61 (Academic)
Bog-trotting for orchids
Niles, Grace Greylock
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Het Leven der Dieren: Deel 1, Hoofdstuk 04: De Roofdieren
Brehm, Alfred Edmund
595 Gutenberg downloadsnl2006
Phylogeny of the Waxwings and Allied Birds
Arvey, M. Dale (Martin Dale)
595 Gutenberg downloadsen2010Difficulty 66 (Academic)
The Mental Life of Monkeys and Apes: A Study of Ideational Behavior
Yerkes, Robert Mearns
595 Gutenberg downloadsen2004Difficulty 61 (Academic)
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
594 Gutenberg downloadsen2022Difficulty 55 (Graduate)
Den Hunting as a Means of Coyote Control
Young, Stanley Paul & Dobyns, Harold Warren
594 Gutenberg downloadsen2015Difficulty 49 (College)
The Naturalist in Nicaragua
Belt, Thomas
594 Gutenberg downloadsen2004Difficulty 63 (Academic)
Animal Life in Field and Garden
Fabre, Jean-Henri
593 Gutenberg downloadsen2021Difficulty 47 (College)
Phrenological Development of Robert Burns From a Cast of His Skull Moulded at Dumfries, the 31st Day of March 1834
Combe, George
593 Gutenberg downloadsen2009Difficulty 58 (Graduate)
The Botanical Magazine, Vol. 13 Or, Flower-Garden Displayed
Curtis, William & Sims, John
593 Gutenberg downloadsen2013Difficulty 58 (Graduate)
The Microscope
Ross, Andrew
593 Gutenberg downloadsen2013Difficulty 65 (Academic)
A Bilateral Division of the Parietal Bone in a Chimpanzee; with a Special Reference to the Oblique Sutures in the Parietal
Hrdlička, Aleš
592 Gutenberg downloadsen2010Difficulty 65 (Academic)
Animal Locomotion; or, walking, swimming, and flying With a dissertation on aëronautics
Pettigrew, James Bell
592 Gutenberg downloadsen2018Difficulty 66 (Academic)
Life Movements in Plants, Volume I
Bose, Jagadis Chandra
591 Gutenberg downloadsen2015Difficulty 69 (Academic)
The Botanical Magazine, Vol. 09 Or, Flower-Garden Displayed
Curtis, William
591 Gutenberg downloadsen2011Difficulty 58 (Graduate)
The history of a mouthful of bread : $b and its effect on the organization of men and animals
Macé, Jean
591 Gutenberg downloadsen2004Difficulty 49 (College)
An Examination of Weismannism
Romanes, George John
590 Gutenberg downloadsen2015Difficulty 74 (Expert)
Links With the Past in the Plant World
Seward, A. C. (Albert Charles)
590 Gutenberg downloadsen2020Difficulty 65 (Academic)
Scientific American Supplement, No. 455, September 20, 1884
Various
590 Gutenberg downloadsen2004Difficulty 57 (Graduate)
Subspeciation in the Meadow Mouse, Microtus pennsylvanicus, in Wyoming, Colorado, and Adjacent Areas
Anderson, Sydney
590 Gutenberg downloadsen2010Difficulty 61 (Academic)
The Gospel of Evolution From "The Atheistic Platform", Twelve Lectures
Aveling, Edward B.
590 Gutenberg downloadsen2011Difficulty 55 (Graduate)
The House Fly and How to Suppress It
Howard, L. O. (Leland Ossian) & Bishopp, F. C. (Fred Corry)
590 Gutenberg downloadsen2006Difficulty 54 (Graduate)
The winners in life's race : $b Or, the great backboned family
Buckley, Arabella B. (Arabella Burton)
590 Gutenberg downloadsen2024Difficulty 63 (Academic)
Himalayan Journals — Volume 1 Or, Notes of a Naturalist in Bengal, the Sikkim and Nepal Himalayas, the Khasia Mountains, etc.
Hooker, Joseph Dalton
589 Gutenberg downloadsen2004Difficulty 74 (Expert)
Noteworthy Mammals from Sinaloa, Mexico
Jones, J. Knox & Alvarez, Ticul & Lee, M. Raymond
589 Gutenberg downloadsen2010Difficulty 52 (Graduate)
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
589 Gutenberg downloadsen2025Difficulty 49 (College)
The Rocky Mountain Goat
Grant, Madison
589 Gutenberg downloadsen2015Difficulty 57 (Graduate)
Bacteria in Daily Life
Frankland, Grace C.
588 Gutenberg downloadsen2013Difficulty 81 (Specialist)
Development of the Digestive Canal of the American Alligator
Reese, A. M. (Albert Moore)
588 Gutenberg downloadsen2007Difficulty 58 (Graduate)
Parallel Paths: A Study in Biology, Ethics, and Art
Rolleston, T. W. (Thomas William)
588 Gutenberg downloadsen2014Difficulty 69 (Academic)
Μικρά Φυσικά, Τόμος Πρώτος
Aristotle
588 Gutenberg downloadsel2009
A Taxonomic Revision of the Leptodactylid Frog Genus Syrrhophus Cope
Lynch, John D.
587 Gutenberg downloadsen2011Difficulty 64 (Academic)
Comments on the Taxonomy and Geographic Distribution of North American Microtines
Hall, E. Raymond (Eugene Raymond) & Cockrum, E. Lendell
587 Gutenberg downloadsen2009Difficulty 62 (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.
586 Gutenberg downloadsen2011Difficulty 50 (College)
Journal of Entomology and Zoology, Vol. 11, No. 4, December 1919
Various
586 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Creierul, O Enigma Descifrata
Moisa, Dorin Teodor
585 Gutenberg downloadsro2004
Fear
Mosso, A. (Angelo)
585 Gutenberg downloadsen2019Difficulty 59 (Graduate)
Evolution and Adaptation
Morgan, Thomas Hunt
584 Gutenberg downloadsen2020Difficulty 62 (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)
584 Gutenberg downloadsen2007Difficulty 57 (Graduate)
Woher die Kindlein kommen
Hoppeler, Hans
584 Gutenberg downloadsde2009
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)
583 Gutenberg downloadsen2024Difficulty 59 (Graduate)
A New Subspecies of Slider Turtle (Pseudemys scripta) from Coahuila, México
Legler, John M.
582 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Geographic variation in red-backed mice (genus Clethrionomys) of the southern Rocky Mountain region
Cockrum, E. Lendell & Fitch, Kenneth Leonard
582 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Subspeciation in Pocket Gophers of Kansas, [KU. Vol. 1 No. 11]
Villa Ramírez, Bernardo & Hall, E. Raymond (Eugene Raymond)
582 Gutenberg downloadsen2011Difficulty 58 (Graduate)
The fauna of the deep sea
Hickson, Sydney J. (Sydney John)
582 Gutenberg downloadsen2021Difficulty 63 (Academic)
The Forest Habitat of the University of Kansas Natural History Reservation
Fitch, Henry S. (Henry Sheldon) & McGregor, Ronald L.
582 Gutenberg downloadsen2010Difficulty 59 (Graduate)
The Social Direction of Evolution: An Outline of the Science of Eugenics
Kellicott, William E. (William Erskine)
582 Gutenberg downloadsen2010Difficulty 63 (Academic)
Het paddenstoelenboekje
Cool, Cath. (Catharina) & Lek, H. A. A. van der (Hendrik Adrianus Abraham)
581 Gutenberg downloadsnl2015
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
581 Gutenberg downloadsen2001Difficulty 61 (Academic)
Variation in the Muscles and Nerves of the Leg in Two Genera of Grouse (Tympanuchus and Pedioecetes)
Holmes, E. Bruce
581 Gutenberg downloadsen2013Difficulty 55 (Graduate)
A Review of the Systems of Ethics Founded on the Theory of Evolution
Williams, Cora May
580 Gutenberg downloadsen2012Difficulty 100 (Quantum Electrodynamics)
Studies of trees in winter : $b A description of the deciduous trees of northeastern America
Huntington, Annie Oakes
580 Gutenberg downloadsen2024Difficulty 51 (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
579 Gutenberg downloadsfr2017
Embryology: The Beginnings of Life
Leighton, Gerald R. (Gerald Rowley)
579 Gutenberg downloadsen2011Difficulty 59 (Graduate)
Myology and Serology of the Avian Family Fringillidae: A Taxonomic Study
Stallcup, William B.
579 Gutenberg downloadsen2010Difficulty 65 (Academic)
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)
579 Gutenberg downloadsen2014Difficulty 54 (Graduate)
The zoology of the voyage of H.M.S. Beagle [vol. 2 of 5] : $b Mammalia
Waterhouse, G. R. (George Robert)
579 Gutenberg downloadsen2022Difficulty 53 (Graduate)
Journal of Entomology and Zoology, Vol. 11, No. 2, June 1919
Various
578 Gutenberg downloadsen2010Difficulty 54 (Graduate)
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
578 Gutenberg downloadsen2010Difficulty 59 (Graduate)
The modes of origin of lowest organisms including a discussion of the experiments of M. Pasteur
Bastian, H. Charlton
578 Gutenberg downloadsen2015Difficulty 71 (Expert)
Scientific American Supplement, No. 601, July 9, 1887
Various
577 Gutenberg downloadsen2004Difficulty 53 (Graduate)
Are the Effects of Use and Disuse Inherited? An Examination of the View Held by Spencer and Darwin
Ball, W. P. (William Platt)
576 Gutenberg downloadsen2008Difficulty 68 (Academic)
British Bees An Introduction into the Studies of the Natural History and Economy of the Bees Indigenous to the British Isles
Shuckard, William Edward
576 Gutenberg downloadsen2017Difficulty 72 (Expert)
Illustrations of Exotic Entomology, Volume 3
Drury, Dru
576 Gutenberg downloadsen2014Difficulty 57 (Graduate)
Introduction to the Study of Palæontological Botany
Balfour, John Hutton
576 Gutenberg downloadsen2016Difficulty 55 (Graduate)
A New Pocket Mouse (Genus Perognathus) from Kansas
Cockrum, E. Lendell
575 Gutenberg downloadsen2010Difficulty 51 (Graduate)
Occurrence of the Garter Snake, Thamnophis sirtalis, in the Great Plains and Rocky Mountains
Fitch, Henry S. (Henry Sheldon) & Maslin, T. Paul
575 Gutenberg downloadsen2010Difficulty 66 (Academic)
Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado
Douglas, Charles L.
574 Gutenberg downloadsen2012Difficulty 63 (Academic)
Schutz- und Trutzbündnisse in der Natur
Bölsche, Wilhelm
574 Gutenberg downloadsde2015
Mushrooms of America, Edible and Poisonous
Unknown
573 Gutenberg downloadsen2009Difficulty 49 (College)
Proceedings of the California Academy of Sciences, Volume III, 1863-1867
Various
573 Gutenberg downloadsen2020Difficulty 58 (Graduate)
Additional Records and Extensions of Known Ranges of Mammals from Utah
Durrant, Stephen David & Hansen, Richard M. & Lee, M. Raymond
572 Gutenberg downloadsen2010Difficulty 57 (Graduate)
The zoology of the voyage of H.M.S. Beagle [vol. 1 of 5] : $b Fossil mammalia
Owen, Richard
571 Gutenberg downloadsen2022Difficulty 58 (Graduate)
Methods of Destroying Rats
Lantz, David E. (David Ernest)
570 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Comments on the Taxonomy and Geographic Distribution of Some North American Rodents
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
569 Gutenberg downloadsen2010Difficulty 56 (Graduate)
Essays of a Biologist
Huxley, Julian
569 Gutenberg downloadsen2021Difficulty 66 (Academic)
Home Range and Movements of the Eastern Cottontail in Kansas
Janes, Donald W.
569 Gutenberg downloadsen2009Difficulty 55 (Graduate)
Intelligence in Plants and Animals Being a New Edition of the Author's Privately Issued "Soul and Immortality."
Gentry, Thomas G. (Thomas George)
569 Gutenberg downloadsen2021Difficulty 71 (Expert)
The Darwinian Hypothesis
Huxley, Thomas Henry
569 Gutenberg downloadsen2001Difficulty 69 (Academic)
Über die Entstehung der Arten im Thier- und Pflanzen-Reich durch natürliche Züchtung
Darwin, Charles
569 Gutenberg downloadsde2022
Fishes of the Big Blue River Basin, Kansas
Minckley, W. L.
568 Gutenberg downloadsen2011Difficulty 47 (College)
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
568 Gutenberg downloadsen2011Difficulty 54 (Graduate)
Physiology and histology of the Cubomedusæ including Dr. F.S. Conant's notes on the physiology
Berger, E. W. (Edward William)
568 Gutenberg downloadsen2017Difficulty 62 (Academic)
Scientific American Supplement, No. 324, March 18, 1882
Various
568 Gutenberg downloadsen2005Difficulty 53 (Graduate)
The Arena, Volume 18, No. 93, August, 1897
Various
568 Gutenberg downloadsen2010Difficulty 51 (Graduate)
The Cubomedusæ
Conant, Franklin Story
568 Gutenberg downloadsen2017Difficulty 60 (Graduate)
The Methods and Scope of Genetics An inaugural lecture delivered 23 October 1908
Bateson, William
568 Gutenberg downloadsen2016Difficulty 60 (Graduate)
Additions to the List of the Birds of Louisiana
Lowery, George H., Jr.
567 Gutenberg downloadsen2010Difficulty 61 (Academic)
An Experimental Translocation of the Eastern Timber Wolf
Weise, Thomas F. & Hook, Richard A. & Mech, L. David & Robinson, William Laughlin
567 Gutenberg downloadsen2011Difficulty 56 (Graduate)
The Universal Kinship
Moore, J. Howard (John Howard)
567 Gutenberg downloadsen2020Difficulty 54 (Graduate)
Fish Populations, Following a Drought, in the Neosho and Marais des Cygnes Rivers of Kansas
Deacon, James E.
566 Gutenberg downloadsen2010Difficulty 52 (Graduate)
General Anatomy, Applied to Physiology and Medicine, Vol. 2 (of 3)
Bichat, Xavier
566 Gutenberg downloadsen2017Difficulty 61 (Academic)
Systematic Status of the Colubrid Snake, Leptodeira discolor Günther
Duellman, William Edward
566 Gutenberg downloadsen2011Difficulty 62 (Academic)
The Mason-Wasps
Fabre, Jean-Henri
566 Gutenberg downloadsen2021Difficulty 50 (College)
Sea-Weeds, Shells and Fossils
Gray, Peter & Woodward, B. B. (Bernard Bolingbroke)
565 Gutenberg downloadsen2011Difficulty 58 (Graduate)
Text book of veterinary medicine, Volume 2 (of 5)
Law, James
565 Gutenberg downloadsen2023Difficulty 66 (Academic)
The chocolate-plant (Theobroma cacao) and its products
Anonymous
565 Gutenberg downloadsen2025Difficulty 55 (Graduate)
The Domestic Cat
Stables, Gordon
565 Gutenberg downloadsen2011Difficulty 51 (Graduate)
The Evolution of Man — Volume 2
Haeckel, Ernst
565 Gutenberg downloadsen2004Difficulty 55 (Graduate)
The human species
Quatrefages, A. de (Armand de)
565 Gutenberg downloadsen2023Difficulty 56 (Graduate)
Eugenics as a Factor in the Prevention of Mental Disease
Pollock, Horatio M. (Horatio Milo)
563 Gutenberg downloadsen2011Difficulty 65 (Academic)
God and the World: A Survey of Thought
Robinson, Arthur William
563 Gutenberg downloadsen2009Difficulty 60 (Graduate)
Influenza : $b An epidemiologic study
Vaughan, Warren T. (Warren Taylor)
563 Gutenberg downloadsen2023Difficulty 66 (Academic)
The Foot-prints of the Creator : $b or, The Asterolepis of Stromness
Miller, Hugh
563 Gutenberg downloadsen2022Difficulty 66 (Academic)
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
562 Gutenberg downloadsen2019Difficulty 68 (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
562 Gutenberg downloadsde2024
Index of the Project Gutenberg Works of Charles Darwin
Darwin, Charles
562 Gutenberg downloadsen2019Difficulty 88 (Specialist)
La simulación en la lucha por la vida
Ingenieros, José
562 Gutenberg downloadses2020
Mammals Obtained by Dr. Curt von Wedel from the Barrier Beach of Tamaulipas, Mexico
Hall, E. Raymond (Eugene Raymond)
562 Gutenberg downloadsen2009Difficulty 53 (Graduate)
Säugethiere vom Celebes- und Philippinen-Archipel
Meyer, Adolf Bernhard
562 Gutenberg downloadsde2023
The giant sequoia : $b An account of the history and characteristics of the big trees of California
Ellsworth, Rodney Sydes
561 Gutenberg downloadsen2025Difficulty 56 (Graduate)
Ameboid movement
Schaeffer, Asa A. (Asa Arthur)
560 Gutenberg downloadsen2017Difficulty 66 (Academic)
Geographic Distribution and Taxonomy of the Chipmunks of Wyoming
White, John A.
560 Gutenberg downloadsen2010Difficulty 50 (College)
The Kansas University Quarterly, Vol. I, No. 1 (1892)
Various
560 Gutenberg downloadsen2017Difficulty 58 (Graduate)
Journal of Entomology and Zoology, Vol. 09, No. 3, September 1917
Various
559 Gutenberg downloadsen2015Difficulty 56 (Graduate)
Nouveaux souvenirs entomologiques - Livre II Étude sur l'instinct et les moeurs des insectes
Fabre, Jean-Henri
559 Gutenberg downloadsfr2006
The botanist's repository for new and rare plants; vol. 01 & 02 [of 10]
Andrews, Henry Cranke, active 1799-1828
559 Gutenberg downloadsen2023Difficulty 57 (Graduate)
Seed Dispersal
Beal, W. J. (William James)
558 Gutenberg downloadsen2008Difficulty 46 (College)
A Review of the Frogs of the Hyla bistincta Group
Duellman, William Edward
557 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Carlo Darwin
Lessona, Michele
557 Gutenberg downloadsit2014
Evolution: An Investigation and a Critique
Graebner, Theodore
557 Gutenberg downloadsen2006Difficulty 62 (Academic)
The Honey-Bee: Its Natural History, Physiology and Management
Bevan, Edward
557 Gutenberg downloadsen2022Difficulty 63 (Academic)
Journal of Entomology and Zoology, Vol. 11, No. 1, March 1919
Various
556 Gutenberg downloadsen2014Difficulty 62 (Academic)
Unsere Haustiere vom Standpunkte ihrer wilden Verwandten
Zell, Th. (Theodor)
556 Gutenberg downloadsde2018
Inorganic Plant Poisons and Stimulants
Brenchley, Winifred Elsie
555 Gutenberg downloadsen2015Difficulty 61 (Academic)
Les énigmes de l'Univers
Haeckel, Ernst
555 Gutenberg downloadsfr2012
Preservation of Bull Semen at Sub-Zero Temperatures
VanDemark, N. L. & Friedman, M. E. & Kinney, W. C. & Miller, W. J. & Rodriguez, Carlos
555 Gutenberg downloadsen2011Difficulty 62 (Academic)
Journal of Entomology and Zoology, Vol. 09, No. 1, March 1917
Various
553 Gutenberg downloadsen2015Difficulty 53 (Graduate)
Mammals of the Grand Mesa, Colorado
Anderson, Sydney
553 Gutenberg downloadsen2010Difficulty 51 (Graduate)
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
553 Gutenberg downloadsen2001Difficulty 64 (Academic)
The Deseado Formation of Patagonia
Loomis, Frederic Brewster
553 Gutenberg downloadsen2024Difficulty 61 (Academic)
Birds and Nature Vol. 09 No. 3 [March 1901]
Various
552 Gutenberg downloadsen2014Difficulty 54 (Graduate)
Jaw Musculature of the Mourning and White-winged Doves
Merz, Robert L.
552 Gutenberg downloadsen2010Difficulty 58 (Graduate)
An Annotated Check List of the Mammals of Michoacán, México
Hall, E. Raymond (Eugene Raymond) & Villa Ramírez, Bernardo
551 Gutenberg downloadsen2012Difficulty 55 (Graduate)
A Statistical Inquiry Into the Nature and Treatment of Epilepsy
Bennett, Alexander Hughes
550 Gutenberg downloadsen2011Difficulty 44 (College)
Die Zelle
Kahn, Fritz
550 Gutenberg downloadsde2012
Mammals taken Along the Alaska Highway
Baker, Rollin H. (Rollin Harold)
550 Gutenberg downloadsen2010Difficulty 47 (College)
Q. E. D., or New Light on the Doctrine of Creation
Price, George McCready
550 Gutenberg downloadsen2004Difficulty 67 (Academic)
The Coal Measures Amphibia of North America
Moodie, Roy Lee
550 Gutenberg downloadsen2019Difficulty 62 (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
549 Gutenberg downloadsen2006Difficulty 57 (Graduate)
Cassell's book of birds; vol. 2
Brehm, Alfred Edmund
549 Gutenberg downloadsen2018Difficulty 58 (Graduate)
International Weekly Miscellany of Literature, Art and Science — Volume 1, No. 2, July 8, 1850
Various
549 Gutenberg downloadsen2004Difficulty 59 (Graduate)
The Atom and the Ocean
Hull, E. W. Seabrook
549 Gutenberg downloadsen2021Difficulty 61 (Academic)
The Evolution Theory, Vol. 2 of 2
Weismann, August
549 Gutenberg downloadsen2021Difficulty 64 (Academic)
Systematics of Megachiropteran Bats in the Solomon Islands
Phillips, Carleton J.
548 Gutenberg downloadsen2012Difficulty 58 (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
548 Gutenberg downloadsen2022Difficulty 63 (Academic)
A New Bat (Genus Pipistrellus) from Northeastern Mexico
Baker, Rollin H. (Rollin Harold)
547 Gutenberg downloadsen2010Difficulty 57 (Graduate)
Greek Biology & Greek Medicine
Singer, Charles
547 Gutenberg downloadsen2020Difficulty 56 (Graduate)
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.
547 Gutenberg downloadsen2010Difficulty 56 (Graduate)
The Speech of Monkeys
Garner, R. L. (Richard Lynch)
547 Gutenberg downloadsen2010Difficulty 54 (Graduate)
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
546 Gutenberg downloadsen2015Difficulty 69 (Academic)
Observations on the Mississippi Kite in Southwestern Kansas
Fitch, Henry S. (Henry Sheldon)
546 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Subspeciation in the Meadow Mouse, Microtus montanus, in Wyoming and Colorado
Anderson, Sydney
546 Gutenberg downloadsen2010Difficulty 50 (College)
The Baculum in the Chipmunks of Western North America
White, John A.
546 Gutenberg downloadsen2010Difficulty 46 (College)
The Factors of Organic Evolution
Spencer, Herbert
546 Gutenberg downloadsen2016Difficulty 70 (Academic)
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
546 Gutenberg downloadsen2001Difficulty 66 (Academic)
Scientific American Supplement, No. 810, July 11, 1891
Various
545 Gutenberg downloadsen2005Difficulty 51 (Graduate)
The Story of Milk
Frederiksen, Johan Ditlev
545 Gutenberg downloadsen2021Difficulty 64 (Academic)
Fossil Butterflies Memoirs of the American Association for the Advancement of Science, I.
Scudder, Samuel Hubbard
544 Gutenberg downloadsen2017Difficulty 59 (Graduate)
Manual of the apiary
Cook, Albert John
544 Gutenberg downloadsen2022Difficulty 49 (College)
Taxonomic Status of Some Mice of The Peromyscus boylii Group in Eastern Mexico, With Description of a New Subspecies
Alvarez, Ticul
544 Gutenberg downloadsen2010Difficulty 52 (Graduate)
The Botanical Magazine, Vol. 03 Or, Flower-Garden Displayed
Curtis, William
544 Gutenberg downloadsen2006Difficulty 57 (Graduate)
The Ohio Journal of Science, Vol. XVI, No. 1, November 1915
Various
544 Gutenberg downloadsen2017Difficulty 50 (College)
Regeneration
Morgan, Thomas Hunt
543 Gutenberg downloadsen2018Difficulty 57 (Graduate)
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
542 Gutenberg downloadsfr2010
Text book of veterinary medicine, Volume 1 (of 5)
Law, James
542 Gutenberg downloadsen2023Difficulty 67 (Academic)
A New Pocket Gopher (Genus Thomomys) From Wyoming and Colorado
Hall, E. Raymond (Eugene Raymond)
541 Gutenberg downloadsen2010Difficulty 51 (Graduate)
The Botanical Magazine, Vol. 08 Or, Flower-Garden Displayed
Curtis, William
541 Gutenberg downloadsen2008Difficulty 60 (Graduate)
The botanist's repository for new and rare plants; vol. 03 & 04 [of 10]
Andrews, Henry Cranke, active 1799-1828
541 Gutenberg downloadsen2024Difficulty 55 (Graduate)
Two New Moles (Genus Scalopus) from Mexico and Texas
Baker, Rollin H. (Rollin Harold)
541 Gutenberg downloadsen2010Difficulty 56 (Graduate)
Vasárnapi Könyv. 1914. Első félév 15. füzet
Various
541 Gutenberg downloadshu2009
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
540 Gutenberg downloadsen2023Difficulty 45 (College)
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
540 Gutenberg downloadsla2012
Two New Meadow Mice from Michoacán Mexico
Hall, E. Raymond (Eugene Raymond)
540 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Harvesting Ants and Trap-Door Spiders Notes and Observations on Their Habits and Dwellings
Moggridge, John Traherne
539 Gutenberg downloadsen2021Difficulty 54 (Graduate)
A bacteriological study of ham souring
McBryde, Charles Neil
538 Gutenberg downloadsen2022Difficulty 59 (Graduate)
Scientific American Supplement, No. 358, November 11, 1882
Various
538 Gutenberg downloadsen2005Difficulty 61 (Academic)
Zeugnisse für die Stellung des Menschen in der Natur
Huxley, Thomas Henry
538 Gutenberg downloadsde2010
An Annotated Checklist of Nebraskan Bats
Webb, Olin L. & Jones, J. Knox
537 Gutenberg downloadsen2010Difficulty 55 (Graduate)
New West Indian Spiders Bulletin of the AMNH, Vol. XXXIII, Art. XLI, pp. 639-642
Banks, Nathan
536 Gutenberg downloadsen2010Difficulty 47 (College)
Der Unterkiefer des Homo Heidelbergensis: Aus den Sanden von Mauer bei Heidelberg
Schoetensack, Otto
535 Gutenberg downloadsde2011
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)
535 Gutenberg downloadsen2008Difficulty 53 (Graduate)
Disease and Its Causes
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534 Gutenberg downloadsen2005Difficulty 57 (Graduate)
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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
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Genera and Subgenera of Chipmunks
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Our Summer Migrants An Account of the Migratory Birds Which Pass the Summer in the British Islands.
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Reise in die Aequinoctial-Gegenden des neuen Continents. Band 4.
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Scientific American Supplement, No. 344, August 5, 1882
Various
532 Gutenberg downloadsen2005Difficulty 54 (Graduate)
Scientific American Supplement, No. 417, December 29, 1883
Various
532 Gutenberg downloadsen2005Difficulty 65 (Academic)
Selected Records of Reptiles and Amphibians from Kansas
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Taxonomy of the Chipmunks, Eutamias quadrivittatus and Eutamias umbrinus
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A New Subspecies of Pocket Mouse from Kansas
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A Synopsis of the American Bats of the Genus Pipistrellus
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Lamarck et son OEuvre
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The Natural History of the Tea-Tree, with Observations on the Medical Qualities of Tea, and on the Effects of Tea-Drinking
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Pleistocene Soricidae from San Josecito Cave, Nuevo Leon, Mexico
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529 Gutenberg downloadsen2010Difficulty 58 (Graduate)
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Various
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Summer Birds From the Yucatan Peninsula, Mexico
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Various
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Journal of Entomology and Zoology, Vol. 06, No. 4, December 1914
Various
527 Gutenberg downloadsen2015Difficulty 53 (Graduate)
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527 Gutenberg downloadsen2024Difficulty 55 (Graduate)
On the origin of inflammation of the veins and of the causes, consequences, and treatment of purulent deposits
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The botanist's repository for new and rare plants; vol. 06 [of 10]
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A New Species of Frog (Genus Tomodactylus) from Western México
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Tentamen Botanicum de Filicum Generibus Dorsiferarum Mémoires de l'Académie Royale des Sciences de Turin vol. 5, 401-422
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De Usu Ratiocinii Mechanici in Medicina
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The Migration of North American Birds (1935)
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A Preliminary Revision of the North American Species of Cactus, Anhalonium, and Lophophora
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519 Gutenberg downloadsen1998Difficulty 56 (Graduate)
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Scientific American Supplement, No. 829, November 21, 1891
Various
518 Gutenberg downloadsen2005Difficulty 63 (Academic)
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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
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512 Gutenberg downloadsen2017Difficulty 76 (Expert)
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Legler, John M.
511 Gutenberg downloadsen2010Difficulty 62 (Academic)
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508 Gutenberg downloadsen2006Difficulty 64 (Academic)
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Salisbury, William
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506 Gutenberg downloadsen2004Difficulty 60 (Graduate)
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Trueb, Linda
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Proceedings of the California Academy of Sciences, Series 3, Volume 4 (Zoology)
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503 Gutenberg downloadsen1998Difficulty 51 (Graduate)
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494 Gutenberg downloadsen2021Difficulty 60 (Graduate)
Scientific American Supplement, No. 613, October 1, 1887
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492 Gutenberg downloadsen2009Difficulty 55 (Graduate)
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485 Gutenberg downloadsen2023Difficulty 49 (College)
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484 Gutenberg downloadsen2010Difficulty 55 (Graduate)
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482 Gutenberg downloadsen2016Difficulty 49 (College)
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482 Gutenberg downloadsen2021Difficulty 70 (Academic)
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481 Gutenberg downloadsen2010Difficulty 62 (Academic)
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481 Gutenberg downloadsen2010Difficulty 55 (Graduate)
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481 Gutenberg downloadsen2020Difficulty 54 (Graduate)
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480 Gutenberg downloadsen2020Difficulty 61 (Academic)
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479 Gutenberg downloadsen2010Difficulty 57 (Graduate)
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478 Gutenberg downloadsen2000Difficulty 66 (Academic)
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477 Gutenberg downloadsen2009Difficulty 58 (Graduate)
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476 Gutenberg downloadsen2024Difficulty 67 (Academic)
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Keys to Fungi on Dung
Richardson, M. J. (Michael J.) & Watling, Roy
476 Gutenberg downloadsen2018Difficulty 57 (Graduate)
Mammals from Southeastern Alaska
Baker, Rollin H. (Rollin Harold) & Findley, James S. (James Smith)
476 Gutenberg downloadsen2010Difficulty 57 (Graduate)
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)
476 Gutenberg downloadsfr2024
Tadarida femorosacca (Merriam) in Tamaulipas, Mexico
Dalquest, Walter Woelber & Hall, E. Raymond (Eugene Raymond)
476 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Adequate Preparation for the Teacher of Biological Sciences in Secondary Schools
McDonald, J. Daley (James Daley)
475 Gutenberg downloadsen2010Difficulty 64 (Academic)
Die Welträtsel: Gemeinverständliche Studien über Monistische Philosophie
Haeckel, Ernst
475 Gutenberg downloadsde2019
Meinauer Naturlehre
Unknown
475 Gutenberg downloadsde2009
A New Chipmunk (Genus Eutamias) from the Black Hills
White, John A.
474 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Pleistocene Pocket Gophers From San Josecito Cave, Nuevo Leon, Mexico
Russell, Robert J.
474 Gutenberg downloadsen2010Difficulty 60 (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
473 Gutenberg downloadsen2021Difficulty 53 (Graduate)
Lehrbuch der Toxikologie für Tierärzte
Fröhner, Eugen
472 Gutenberg downloadsde2022
Measles
Rucker, William Colby
472 Gutenberg downloadsen2006Difficulty 50 (College)
Marxism and Darwinism : $b Evidence, speeches, and papers in its favour
Pannekoek, Anton
471 Gutenberg downloadsen2023Difficulty 58 (Graduate)
Über die Vulkane im Monde
Kant, Immanuel
471 Gutenberg downloadsde2012
Agricultural zoology
Ritzema Bos, J. (Jan)
470 Gutenberg downloadsen2025Difficulty 52 (Graduate)
Der Tabak: Studien über seine Kultur und Biologie
Koning, C. J. (Cornelis Johan)
470 Gutenberg downloadsde2016
The Structure and Habits of Spiders
Emerton, J. H. (James Henry)
470 Gutenberg downloadsen2018Difficulty 44 (College)
Uit de dierenwereld van het water Schetsen in woord en beeld van het lever der lagere diersoorten
Snijders, A. J. C. (Anthony J. C.)
470 Gutenberg downloadsnl2022
A New Pocket Gopher (Thomomys) and A New Spiny Pocket Mouse (Liomys) from Michoacán, Mexico
Hall, E. Raymond (Eugene Raymond) & Villa Ramírez, Bernardo
469 Gutenberg downloadsen2010Difficulty 60 (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)
469 Gutenberg downloadsen2020Difficulty 67 (Academic)
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)
469 Gutenberg downloadsen2019Difficulty 61 (Academic)
The Subspecies of the Mountain Chickadee
Grinnell, Joseph
468 Gutenberg downloadsen2010Difficulty 50 (College)
De Plantis Esculentis Insularum Oceani Australis Commentatio Botanica
Forster, Georg
467 Gutenberg downloadsla2011
The honey bee: a manual of instruction in apiculture
Benton, Frank
467 Gutenberg downloadsen2022Difficulty 55 (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
466 Gutenberg downloadsen2010Difficulty 49 (College)
Le Tour du Monde; Voyage d'un naturaliste. Journal des voyages et des voyageurs; 2. sem. 1860
Various
466 Gutenberg downloadsfr2008
The heathery; or, A monograph of the genus Erica. vol. 1
Andrews, Henry Cranke, active 1799-1828
466 Gutenberg downloadsen2022Difficulty 52 (Graduate)
Food of the Crow, Corvus brachyrhynchos Brehm, in South-central Kansas
Platt, Dwight R.
465 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Cholera and the Water Supply in the South Districts of London in 1854
Snow, John
464 Gutenberg downloadsen2021Difficulty 71 (Expert)
Records of Harvest Mice, Reithrodontomys, from Central America, with Description of a New Subspecies from Nicaragua
Anderson, Sydney & Jones, J. Knox
464 Gutenberg downloadsen2010Difficulty 55 (Graduate)
Useful Knowledge: Volume 3. Animals Or, a familiar account of the various productions of nature
Bingley, William
464 Gutenberg downloadsen2018Difficulty 54 (Graduate)
Descriptions of Two Species of Frogs, Genus Ptychohyla Studies of American Hylid Frogs, V
Duellman, William Edward
463 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Pipistrellus cinnamomeus Miller 1902 Referred to the Genus Myotis
Hall, E. Raymond (Eugene Raymond) & Dalquest, Walter Woelber
463 Gutenberg downloadsen2010Difficulty 55 (Graduate)
The Hunterian lectures on colour-vision and colour-blindness
Edridge-Green, F. W. (Frederick William)
463 Gutenberg downloadsen2025Difficulty 56 (Graduate)
The Mammals of Washtenaw County, Michigan Occasional Papers of the Museum of Zoology, No. 123
Wood, Norman Asa
463 Gutenberg downloadsen2010Difficulty 44 (College)
Five Natural Hybrid Combinations in Minnows (Cyprinidae)
Cross, Frank B. (Frank Bernard) & Minckley, W. L.
462 Gutenberg downloadsen2011Difficulty 55 (Graduate)
The Doctrine of Evolution: Its Basis and Its Scope
Crampton, Henry Edward
462 Gutenberg downloadsen2005Difficulty 65 (Academic)
The Tadpoles of Bufo cognatus Say
Smith, Hobart M. (Hobart Muir)
461 Gutenberg downloadsen2010Difficulty 54 (Graduate)
Coloured engravings of heaths; vol. 1
Andrews, Henry Cranke, active 1799-1828
460 Gutenberg downloadsen2023Difficulty 60 (Graduate)
Die krankheiterregenden Bakterien Entstehung, Heilung und Bekämpfung der bakteriellen Infektionskrankheiten des Menschen
Löhlein, Max
460 Gutenberg downloadsde2017
Ilex cassine, the aboriginal North American tea $b Its history, distribution, and use among the native North American Indians
Hale, Edwin M. (Edwin Moses)
460 Gutenberg downloadsen2023Difficulty 52 (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
460 Gutenberg downloadsen2015Difficulty 68 (Academic)
A New Subspecies of the Fruit-eating Bat, Sturnira ludovici, From Western Mexico
Jones, J. Knox & Phillips, Gary L.
459 Gutenberg downloadsen2010Difficulty 55 (Graduate)
The house we live in : $b or, The making of the body
Farnsworth, Vesta J. (Vesta Jane)
459 Gutenberg downloadsen2021Difficulty 31 (High School)
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
458 Gutenberg downloadsde2008
The Birds of Australia, Vol. 2 of 7
Gould, John
458 Gutenberg downloadsen2019Difficulty 66 (Academic)
The case against evolution
O'Toole, George Barry
458 Gutenberg downloadsen2022Difficulty 69 (Academic)
Degeneration: A Chapter in Darwinism
Lankester, E. Ray (Edwin Ray), Sir
456 Gutenberg downloadsen2019Difficulty 66 (Academic)
New England Salmon Hatcheries and Salmon Fisheries in the Late 19th Century
Various
456 Gutenberg downloadsen2005Difficulty 53 (Graduate)
Some Common Birds Useful to the Farmer (1915 edition)
Beal, F. E. L. (Foster Ellenborough Lascelles)
456 Gutenberg downloadsen2020Difficulty 54 (Graduate)
Studies of Birds Killed in Nocturnal Migration
Tordoff, Harrison Bruce & Mengel, Robert Morrow
456 Gutenberg downloadsen2016Difficulty 54 (Graduate)
De la télépathie: Étude sur la transmission de la pensée
Hureau, Émile
455 Gutenberg downloadsfr2006
Studies in the Evolutionary Psychology of Feeling
Stanley, Hiram Miner
455 Gutenberg downloadsen2018Difficulty 62 (Academic)
Natural History of the Salamander, Aneides hardii
Johnston, Richard F. & Schad, G. A.
454 Gutenberg downloadsen2010Difficulty 59 (Graduate)
Noções botanicas das especies de Nicociana mais usadas nas fabricas de tabaco, e da sua cultura
Unknown
454 Gutenberg downloadspt2012
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
453 Gutenberg downloadsen2017Difficulty 61 (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
452 Gutenberg downloadsen2018Difficulty 58 (Graduate)
Coloured engravings of heaths; vol. 4
Andrews, Henry Cranke, active 1799-1828
452 Gutenberg downloadsen2023Difficulty 60 (Graduate)
Palæontological Report of the Princeton Scientific Expedition of 1877
Osborn, Henry Fairfield & Scott, William Berryman & Speir, Francis
452 Gutenberg downloadsen2021Difficulty 56 (Graduate)
Studies on Epidemic Influenza: Comprising Clinical and Laboratory Investigations
University of Pittsburgh. School of Medicine
452 Gutenberg downloadsen2019Difficulty 62 (Academic)
Water Reptiles of the Past and Present
Williston, Samuel Wendell
452 Gutenberg downloadsen2022Difficulty 63 (Academic)
Aspects of plant life; with special reference to the British flora
Praeger, R. Lloyd (Robert Lloyd)
451 Gutenberg downloadsen2018Difficulty 59 (Graduate)
The Meaning of Infancy
Fiske, John
451 Gutenberg downloadsen2004Difficulty 62 (Academic)
Flytraps and Their Operation [1930]
Bishopp, F. C. (Fred Corry)
450 Gutenberg downloadsen2020Difficulty 51 (Graduate)
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)
449 Gutenberg downloadsen2024Difficulty 66 (Academic)
Systematic Status of a South American Frog, Allophryne ruthveni Gaige
Lynch, John D. & Freeman, Howard L.
449 Gutenberg downloadsen2010Difficulty 63 (Academic)
Popular Lectures on Zoonomia Or The Laws of Animal Life, in Health and Disease
Garnett, Thomas
448 Gutenberg downloadsen2009Difficulty 59 (Graduate)
Lajien synty: Luonnollisen valinnan kautta
Darwin, Charles
447 Gutenberg downloadsfi2016
Whale Primer, with Special Attention to the California Gray Whale
Walker, Theodore J.
447 Gutenberg downloadsen2019Difficulty 55 (Graduate)
A New Bat (Genus Myotis) From Mexico
Dalquest, Walter Woelber & Hall, E. Raymond (Eugene Raymond)
446 Gutenberg downloadsen2010Difficulty 57 (Graduate)
A New Hylid Frog from Eastern Mexico. University of Kansas Publication, Vol 1, No 15
Taylor, Edward Harrison
446 Gutenberg downloadsen2010Difficulty 62 (Academic)
From an Easy Chair
Lankester, E. Ray (Edwin Ray), Sir
446 Gutenberg downloadsen2020Difficulty 50 (College)
Het Leven der Dieren: Deel 1, Hoofdstuk 01: De Apen
Brehm, Alfred Edmund
446 Gutenberg downloadsnl2005
Het Leven der Dieren: Deel 1, Hoofdstuk 12: Sirenen; Hoofdstuk 13: Walvischachtigen
Brehm, Alfred Edmund
446 Gutenberg downloadsnl2007
A Defence of the Inquiry into Mesmerism & Phrenology chiefly in relation to recent events in Lynn
Armes, William
445 Gutenberg downloadsen2017Difficulty 66 (Academic)
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
445 Gutenberg downloadspt2005
Determining the Age of Cattle by the Teeth
Pope, George W. (George Whitfield)
445 Gutenberg downloadsen2008Difficulty 52 (Graduate)
Insect manufactures
Anonymous
445 Gutenberg downloadsen2024Difficulty 60 (Graduate)
Sanitation in Panama
Gorgas, William Crawford
445 Gutenberg downloadsen2023Difficulty 56 (Graduate)
An Essay on the Effects of Opium. Considered as a Poison
Awsiter, John
444 Gutenberg downloadsen2016Difficulty 75 (Expert)
The Subspecies of the Mexican Red-Bellied Squirrel, Sciurus aureogaster
Kelson, Keith R.
444 Gutenberg downloadsen2010Difficulty 61 (Academic)
Conspecificity of two pocket mice, Perognathus goldmani and P. artus
Hall, E. Raymond (Eugene Raymond) & Ogilvie, Marilyn Bailey
443 Gutenberg downloadsen2010Difficulty 53 (Graduate)
The heathery; or, A monograph of the genus Erica. vol. 3
Andrews, Henry Cranke, active 1799-1828
443 Gutenberg downloadsen2023Difficulty 56 (Graduate)
A New Subspecies of Bat (Myotis velifer) from Southeastern California and Arizona
Vaughan, Terry A.
442 Gutenberg downloadsen2010Difficulty 56 (Graduate)
Phrenology Examined
Flourens, P. (Pierre)
442 Gutenberg downloadsen2021Difficulty 59 (Graduate)
Observations on the Terataspis grandis, Hall, the largest known trilobite
Clarke, John Mason
441 Gutenberg downloadsen2022Difficulty 60 (Graduate)
Two New Pelycosaurs from the Lower Permian of Oklahoma
Fox, Richard C.
441 Gutenberg downloadsen2009Difficulty 59 (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
439 Gutenberg downloadspt2012
Sphinx Vespiformis: An Essay
Newman, Edward
438 Gutenberg downloadsen2013Difficulty 73 (Expert)
A New Name for the Mexican Red Bat
Hall, E. Raymond (Eugene Raymond)
437 Gutenberg downloadsen2007Difficulty 55 (Graduate)
Sciências Naturaes Pela Redacção da «Educação Nacional»
Anonymous
437 Gutenberg downloadspt2006
Stray Feathers From a Bird Man's Desk
Rand, Austin Loomer
437 Gutenberg downloadsen2021Difficulty 54 (Graduate)
The genetic and the operative evidence relating to secondary sexual characters
Morgan, Thomas Hunt
437 Gutenberg downloadsen2018Difficulty 47 (College)
The philosophy of biology
Johnstone, James
437 Gutenberg downloadsen2020Difficulty 65 (Academic)
A history of evolution
Fenton, Carroll Lane
436 Gutenberg downloadsen2025Difficulty 63 (Academic)
Das Protistenreich : $b eine populäre Uebersicht über das Formengebiet der niedersten Lebewesen; Mit einem wissenschaftlichen Anhange: System der Protisten
Haeckel, Ernst
436 Gutenberg downloadsde2025
Die Naturwissenschaften in ihrer Entwicklung und in ihrem Zusammenhange, IV. Band Das Emporblühen der modernen Naturwissenschaften seit der Entdeckung des Energieprinzips
Dannemann, Friedrich
436 Gutenberg downloadsde2019
Den Waaragtigen Omloop des Bloeds
Leeuwenhoek, Antoni van
435 Gutenberg downloadsnl2006
La vie des termites
Maeterlinck, Maurice
435 Gutenberg downloadsfr2024
Μικρά Φυσικά, Τόμος Δεύτερος
Aristotle
435 Gutenberg downloadsel2009
Geographic Variation in the North American Cyprinid Fish, Hybopsis gracilis
Olund, Leonard J. & Cross, Frank B. (Frank Bernard)
433 Gutenberg downloadsen2011Difficulty 57 (Graduate)
Heroes of science : $b Botanists, zoologists, and geologists
Duncan, P. Martin (Peter Martin)
433 Gutenberg downloadsen2023Difficulty 58 (Graduate)
Irritability : $b a physiological analysis of the general effect of stimuli in living substance
Verworn, Max
433 Gutenberg downloadsen2021Difficulty 65 (Academic)
The botanist's repository for new and rare plants; vol. 07 [of 10]
Andrews, Henry Cranke, active 1799-1828
433 Gutenberg downloadsen2024Difficulty 57 (Graduate)
A New Genus of Pennsylvanian Fish (Crossopterygii, Coelacanthiformes) from Kansas
Echols, Joan
432 Gutenberg downloadsen2010Difficulty 60 (Graduate)
De afstamming van den mensch Naar voordrachten in populair-wetenschappelijken vorm bewerkt
Boeke, Jan
431 Gutenberg downloadsnl2017
La philosophie zoologique avant Darwin
Perrier, Edmond
430 Gutenberg downloadsfr2010
Colour vision : $b Being the Tyndall Lectures delivered in 1894 at the Royal Institution
Abney, William de Wiveleslie, Sir
429 Gutenberg downloadsen2024Difficulty 55 (Graduate)
Geographic Variation in the Harvest Mouse, Reithrodontomys megalotis, On the Central Great Plains And in Adjacent Regions
Jones, J. Knox & Mursaloglu, B.
429 Gutenberg downloadsen2009Difficulty 56 (Graduate)
Morphological Variation in a Population of the Snake, Tantilla gracilis Baird and Girard
Hardy, Laurence M. & Cole, Charles J.
429 Gutenberg downloadsen2010Difficulty 55 (Graduate)
The Birds of Australia, Vol. 3 of 7
Gould, John
429 Gutenberg downloadsen2019Difficulty 61 (Academic)
Roses: or, a Monograph of the Genus Rosa
Andrews, Henry Cranke, active 1799-1828
428 Gutenberg downloadsen2021Difficulty 63 (Academic)
The Bedbug [1934]
Marlatt, C. L.
428 Gutenberg downloadsen2020Difficulty 62 (Academic)
The botanist's repository for new and rare plants; vol. 08 [of 10]
Andrews, Henry Cranke, active 1799-1828
428 Gutenberg downloadsen2024Difficulty 58 (Graduate)
A New Bat (Genus Leptonycteris) From Coahuila
Stains, Howard J.
427 Gutenberg downloadsen2010Difficulty 53 (Graduate)
Dans la Haute-Gambie : $b Voyage d'exploration scientifique, 1891-1892
Rançon, A. (André)
427 Gutenberg downloadsfr2024
Von Sonnen und Sonnenstäubchen : $b Kosmische Wanderungen
Bölsche, Wilhelm
427 Gutenberg downloadsde2025
The micro-organisms of the soil
Russell, Edward J. (Edward John) & Rothamsted Experimental Station
426 Gutenberg downloadsen2022Difficulty 62 (Academic)
A New Subspecies of Microtus montanus from Montana and Comments on Microtus canicaudus Miller
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
425 Gutenberg downloadsen2009Difficulty 58 (Graduate)
Botanical features of the Algerian Sahara
Cannon, William Austin
425 Gutenberg downloadsen2023Difficulty 52 (Graduate)
De honig en zijn gebruik
Rondou, W.-F.
425 Gutenberg downloadsnl2008
Descripção de algumas especies novas ou pouco conhecidas de crustaceos e arachnidios de Portugal e possessões portuguezas do ultramar
Capello, Felix Antonio de Brito
425 Gutenberg downloadsfr2010
Emanuel Swedenborg's Investigations in Natural Science and the Basis for His Statements Concerning the Functions of the Brain
Ramström, Martin
425 Gutenberg downloadsen2020Difficulty 71 (Expert)
History of biology
Miall, L. C. (Louis Compton)
425 Gutenberg downloadsen2018Difficulty 61 (Academic)
On The Affinities of Leptarctus primus of Leidy American Museum of Natural History, Vol. VI, Article VIII, pp. 229-331.
Wortman, Jacob Lawson
424 Gutenberg downloadsen2008Difficulty 54 (Graduate)
The Philosophy of Evolution Together With a Preliminary Essay on The Metaphysical Basis of Science
Carpenter, Stephen H. (Stephen Haskins)
424 Gutenberg downloadsen2009Difficulty 64 (Academic)
Archimedes; or, the future of physics
Whyte, Lancelot Law
423 Gutenberg downloadsen2025Difficulty 66 (Academic)
Biological analogies in history
Roosevelt, Theodore
422 Gutenberg downloadsen2023Difficulty 70 (Academic)
The Botanical Magazine, Vol. 10 Or, Flower-Garden Displayed
Curtis, William
422 Gutenberg downloadsen2020Difficulty 57 (Graduate)
Supplement to Harvesting Ants and Trap-Door Spiders
Moggridge, John Traherne & Pickard-Cambridge, Octavius
420 Gutenberg downloadsen2021Difficulty 59 (Graduate)
Contagious Abortion of Cows
MacNeal, Ward J.
419 Gutenberg downloadsen2011Difficulty 66 (Academic)
Illustrations of the birds of Jamaica
Gosse, Philip Henry
418 Gutenberg downloadsen2024Difficulty 48 (College)
Little Wanderers
Morley, Margaret Warner
418 Gutenberg downloadsen2020Difficulty 41 (College)
An Estimate of the True Value of Vaccination as a Security Against Small Pox
Greenhow, T. M. (Thomas Michael)
417 Gutenberg downloadsen2015Difficulty 70 (Academic)
Aus dem Leben der Insekten
Buckley, Arabella B. (Arabella Burton)
417 Gutenberg downloadsde2022
Mammals Collected by Dr. W. L. Abbott on the Natuna Islands Proceedings of the Washington Academy of Sciences, Vol. III, pp. 111-138
Miller, Gerrit S. (Gerrit Smith)
417 Gutenberg downloadsen2014Difficulty 54 (Graduate)
La espressione dei sentimenti dei nostri volatili domestici
Pascal, Teodoro
416 Gutenberg downloadsit2017
Some Common Birds in Their Relation to Agriculture
Beal, F. E. L. (Foster Ellenborough Lascelles)
416 Gutenberg downloadsen2020Difficulty 55 (Graduate)
The Philosophy of Health; Volume 1 (of 2) or, an exposition of the physical and mental constitution of man
Smith, Southwood
416 Gutenberg downloadsen2019Difficulty 73 (Expert)
Natural History of the Brush Mouse (Peromyscus boylii) in Kansas With Description of a New Subspecies
Long, Charles Alan
415 Gutenberg downloadsen2010Difficulty 51 (Graduate)
Supplement to the catalogue of seals and whales in the British Museum
Gray, John Edward
415 Gutenberg downloadsen2023Difficulty 45 (College)
Two New Pocket Gophers from Wyoming and Colorado
Hall, E. Raymond (Eugene Raymond) & Montague, H. Gordon
414 Gutenberg downloadsen2009Difficulty 51 (Graduate)
Bedenkingen tegen de Leer van Darwin Gevolgd door beschouwingen over eenige philosophische onderwerpen.
Reuther, Antoine Charles
413 Gutenberg downloadsnl2009
Leprosy : $b in its clinical & pathological aspects
Hansen, G. Armauer (Gerhard Armauer) & Looft, Carl
413 Gutenberg downloadsen2023Difficulty 64 (Academic)
Poisonous Snakes of Kansas
Clarke, Robert F. (Robert Francis)
413 Gutenberg downloadsen2019Difficulty 50 (College)
Preliminary Survey of a Paleocene Faunule from the Angels Peak Area, New Mexico
Wilson, Robert W. (Robert Warren)
413 Gutenberg downloadsen2010Difficulty 62 (Academic)
Proefnemingen van de particuliere beweeging der spieren in de kikvorsch
Swammerdam, Jan
413 Gutenberg downloadsnl2006
The Subspecific Status of Two Central American Sloths
Hall, E. Raymond (Eugene Raymond) & Kelson, Keith R.
413 Gutenberg downloadsen2010Difficulty 62 (Academic)
Der Ameisenlöwe : $b eine biologische, tierpsychologische und reflexbiologische Untersuchung
Doflein, Franz
411 Gutenberg downloadsde2025
Het Leven der Dieren: Deel 1, Hoofdstuk 07: De Knaagdieren
Brehm, Alfred Edmund
411 Gutenberg downloadsnl2007
Flytraps and Their Operation [1921]
Bishopp, F. C. (Fred Corry)
410 Gutenberg downloadsen2020Difficulty 48 (College)
Het Leven der Dieren: Deel 2, Hoofdstuk 04: De Hoendervogels
Brehm, Alfred Edmund
410 Gutenberg downloadsnl2009
Self-Organizing Systems, 1963
Unknown
410 Gutenberg downloadsen2021Difficulty 72 (Expert)
Catalogue of the dipterous insects collected at Singapore and Malacca
Wallace, Alfred Russel
409 Gutenberg downloadsen2023Difficulty 56 (Graduate)
Kyphosis and other Variations in Soft-shelled Turtles
Smith, Hobart M. (Hobart Muir)
409 Gutenberg downloadsen2010Difficulty 46 (College)
Profitable poultry : $b Their management in health and disease
Tegetmeier, W. B. (William Bernhard)
409 Gutenberg downloadsen2024Difficulty 65 (Academic)
The Lives of Celebrated Travellers, Vol. 2 (of 3)
St. John, James Augustus
408 Gutenberg downloadsen2021Difficulty 90 (Specialist)
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
407 Gutenberg downloadsen2014Difficulty 50 (College)
Evolution Social and Organic
Lewis, Arthur M. (Arthur Morrow)
407 Gutenberg downloadsen2018Difficulty 57 (Graduate)
Hormones and Heredity A Discussion of the Evolution of Adaptations and the Evolution of Species
Cunningham, J. T. (Joseph Thomas)
407 Gutenberg downloadsen2005Difficulty 73 (Expert)
The Bedbug [1916]
Marlatt, C. L.
407 Gutenberg downloadsen2020Difficulty 61 (Academic)
Geographic Distribution of the Pocket Mouse, Perognathus fasciatus
Jones, J. Knox
406 Gutenberg downloadsen2010Difficulty 58 (Graduate)
The flowering plants of South Africa; vol. 2
Unknown
405 Gutenberg downloadsen2021Difficulty 51 (Graduate)
Biology versus Theology. The Bible: irreconcilable with Science, Experience, and even its own statements
Julian
403 Gutenberg downloadsen2021Difficulty 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
403 Gutenberg downloadsen2019Difficulty 48 (College)
Evolution made plain
Mason, John (John Harmon)
402 Gutenberg downloadsen2025Difficulty 55 (Graduate)
The pathology of influenza
Winternitz, M. C. (Milton C.) & McNamara, Frank P. & Wason, Isabel M.
402 Gutenberg downloadsen2019Difficulty 69 (Academic)
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Lönnrot, Elias
400 Gutenberg downloadsfi2017
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)
400 Gutenberg downloadsen2024Difficulty 54 (Graduate)
The plurality of the human race
Pouchet, G. (Georges)
400 Gutenberg downloadsen2023Difficulty 61 (Academic)
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
400 Gutenberg downloadsen2015Difficulty 67 (Academic)
The Salmon Fishery of Penobscot Bay and River in 1895-96
Smith, Hugh M. (Hugh McCormick)
399 Gutenberg downloadsen2005Difficulty 48 (College)
Epidemics Examined and Explained: or, Living Germs Proved by Analogy to be a Source of Disease
Grove, John
398 Gutenberg downloadsen2010Difficulty 65 (Academic)
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Maeterlinck, Maurice
398 Gutenberg downloadsfr2020
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
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Poultry diseases Causes, symptoms and treatment, with notes on post-mortem examinations
Wortley, E. J. (E. Jocelyn)
396 Gutenberg downloadsen2022Difficulty 57 (Graduate)
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
396 Gutenberg downloadsen2021Difficulty 43 (College)
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Brehm, Alfred Edmund
395 Gutenberg downloadsnl2009
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Rosburg, David W. & King, D. R.
395 Gutenberg downloadsen2021Difficulty 64 (Academic)
Pliocene and Pleistocene Records of Fossil Turtles from Western Kansas and Oklahoma University of Kansas Publications Museum of Natural History Volume 1
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395 Gutenberg downloadsen2010Difficulty 60 (Graduate)
Report on the Migration of Birds in the Spring and Autumn of 1883. Fifth Report
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395 Gutenberg downloadsen2021Difficulty 44 (College)
The heathery; or, A monograph of the genus Erica. vol. 2
Andrews, Henry Cranke, active 1799-1828
394 Gutenberg downloadsen2023Difficulty 54 (Graduate)
A Monograph of the Trilobites of North America: with Coloured Models of the Species
Green, Jacob
393 Gutenberg downloadsen2021Difficulty 63 (Academic)
The Christian Foundation, Or, Scientific and Religious Journal, Volume 1, Index, 1880
Various
393 Gutenberg downloadsen2009Difficulty 77 (Expert)
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391 Gutenberg downloadsnl2025
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391 Gutenberg downloadsen2022Difficulty 69 (Academic)
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Björklund, Gustaf
390 Gutenberg downloadsen2019Difficulty 58 (Graduate)
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389 Gutenberg downloadsen2011Difficulty 60 (Graduate)
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Legler, John M.
388 Gutenberg downloadsen2010Difficulty 63 (Academic)
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388 Gutenberg downloadsen2010Difficulty 54 (Graduate)
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Morgan, Thomas Hunt
388 Gutenberg downloadsen2023Difficulty 57 (Graduate)
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North, Roger
388 Gutenberg downloadsen2021Difficulty 47 (College)
The heathery; or, A monograph of the genus Erica. vol. 4
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387 Gutenberg downloadsen2023Difficulty 56 (Graduate)
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386 Gutenberg downloadsen2011Difficulty 57 (Graduate)
The Birds of Australia, Vol. 4 of 7
Gould, John
384 Gutenberg downloadsen2019Difficulty 64 (Academic)
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383 Gutenberg downloadsnl2007
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Buckley, Arabella B. (Arabella Burton)
381 Gutenberg downloadsde2022
Relics of Primeval Life: Beginning of Life in the Dawn of Geological Time
Dawson, John William, Sir
380 Gutenberg downloadsen2022Difficulty 58 (Graduate)
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377 Gutenberg downloadsnl2014
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Monro, Alexander
376 Gutenberg downloadsen2014Difficulty 66 (Academic)
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Hopkins, Cyril G. (Cyril George)
376 Gutenberg downloadsen2018Difficulty 58 (Graduate)
Some Common Birds Useful to the Farmer (1926 edition)
Beal, F. E. L. (Foster Ellenborough Lascelles)
376 Gutenberg downloadsen2020Difficulty 55 (Graduate)
The Kansas University Science Bulletin, Vol. I, No. 2, February, 1902
Various
376 Gutenberg downloadsen2017Difficulty 52 (Graduate)
Zwischen Pol und Äquator: Tiergeographische Lebensbilder
Floericke, Kurt
376 Gutenberg downloadsde2022
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Burckhardt, Rudolf
374 Gutenberg downloadsde2024
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Jacob, Edward Henry
373 Gutenberg downloadsen2023Difficulty 50 (College)
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Bölsche, Wilhelm
373 Gutenberg downloadsde2018
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373 Gutenberg downloadsnl2007
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Vallot, Joseph
373 Gutenberg downloadsfr2024
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Hollman, Pierre Jean
372 Gutenberg downloadsnl2010
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Coker, R. E. (Robert Ervin)
371 Gutenberg downloadsen2013Difficulty 65 (Academic)
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Hollingworth, Harry L. (Harry Levi) & Poffenberger, Albert T. (Albert Theodore)
371 Gutenberg downloadsen2019Difficulty 69 (Academic)
An Attempt to Investigate the Seat of Animal Life
Curtis, Henry
370 Gutenberg downloadsen2021Difficulty 71 (Expert)
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369 Gutenberg downloadsnl2023
The Ohio naturalist, Vol. 1, No. 3, January, 1901
Ohio State University. Biological Club
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Darwinism. The Noachian Flood A lecture delivered before the Torquay Natural History Society, Jan. 31st, 1870
Stebbing, Thomas Roscoe Rede
368 Gutenberg downloadsen2021Difficulty 68 (Academic)
The Kansas University science bulletin, Vol. I, No. 8, September 1902
Unknown
368 Gutenberg downloadsen2023Difficulty 64 (Academic)
Evolution
Hoare, Edward
366 Gutenberg downloadsen2016Difficulty 55 (Graduate)
The Anatomy of Vegetables Begun With a General Account of Vegetation founded thereon
Grew, Nehemiah
365 Gutenberg downloadsen2018Difficulty 48 (College)
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Tarré, Emili
364 Gutenberg downloadsca2024
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363 Gutenberg downloadsnl2009
The heathery; or, A monograph of the genus Erica. vol. 5
Andrews, Henry Cranke, active 1799-1828
363 Gutenberg downloadsen2023Difficulty 56 (Graduate)
De koraal-eilanden: fragment uit het dagboek van een natuuronderzoeker De Aarde en haar Volken, 1875
Darwin, Charles
362 Gutenberg downloadsnl2015
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Bölsche, Wilhelm
362 Gutenberg downloadsnl2025
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Various
362 Gutenberg downloadsen2018Difficulty 53 (Graduate)
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United States. Public Health Service
362 Gutenberg downloadsen2023Difficulty 60 (Graduate)
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
360 Gutenberg downloadsen2021Difficulty 41 (College)
Bee-keeping for profit
Morley, W. S.
359 Gutenberg downloadsen2022Difficulty 53 (Graduate)
Coloured engravings of heaths; vol. 3
Andrews, Henry Cranke, active 1799-1828
356 Gutenberg downloadsen2023Difficulty 66 (Academic)
The Orchid Album, Volume 3 Comprising Coloured Figures and Descriptions of New, Rare, and Beautiful Orchidaceous Plants
Moore, Thomas
356 Gutenberg downloadsen2019Difficulty 57 (Graduate)
Het Leven der Dieren: Deel 3.7, De Weekdieren
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355 Gutenberg downloadsnl2020
The Ohio naturalist, Vol. 1, No. 8, June 1901
Ohio State University. Biological Club
355 Gutenberg downloadsen2022Difficulty 51 (Graduate)
Het Leven der Dieren: Deel 1, Hoofdstuk 05: Robben; Hoofdstuk 06: Insecteneters
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354 Gutenberg downloadsnl2006
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De Harmonie van het Dierlijke Leven: De Openbaring van Wetten
Donders, F. C. (Franciscus Cornelis)
353 Gutenberg downloadsnl2005
Foreign Butterflies
Duncan, James
353 Gutenberg downloadsen2018Difficulty 56 (Graduate)
Het Leven der Dieren, Deel 3, Hoofdstuk 6: De Wormen
Brehm, Alfred Edmund
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Heimans, Eli & Thijsse, Jac. P. (Jacobus Pieter)
353 Gutenberg downloadsnl2022
The Ohio naturalist, Vol. 1, No. 4, February 1901
Ohio State University. Biological Club
353 Gutenberg downloadsen2022Difficulty 49 (College)
A Guide for the Dissection of the Dogfish (Squalus Acanthias)
Griffin, Lawrence Edmonds
352 Gutenberg downloadsen2019Difficulty 54 (Graduate)
Het Leven der Dieren: Deel 2, Hoofdstuk 02: De Papegaaien; Hoofdstuk 03: De Duifvogels
Brehm, Alfred Edmund
352 Gutenberg downloadsnl2009
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
351 Gutenberg downloadsen2018Difficulty 65 (Academic)
Four New Pocket Gophers of the Genus Cratogeomys from Jalisco, Mexico
Russell, Robert J.
350 Gutenberg downloadsen2010Difficulty 61 (Academic)
The illustrated story of evolution
Gauvin, Marshall J. (Marshall Jerome)
350 Gutenberg downloadsen2023Difficulty 54 (Graduate)
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
349 Gutenberg downloadsen2022Difficulty 64 (Academic)
The Ohio Naturalist, Vol. I, No. 7, May, 1901
Ohio State University. Biological Club
349 Gutenberg downloadsen2023Difficulty 51 (Graduate)
Fauna der Nassauischen Mollusken
Kobelt, Wilhelm
348 Gutenberg downloadsde2015
Über den Bildungstrieb
Blumenbach, Johann Friedrich
347 Gutenberg downloadsde2020
A Statement of Facts Tending to Establish an Estimate of the True Value and Present State of Vaccination
Blane, Gilbert, Sir
346 Gutenberg downloadsen2022Difficulty 67 (Academic)
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Palmén, J. A. (Johan Axel)
346 Gutenberg downloadsfi2024
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Anonymous
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The Virtue and Use of Coffee With Regard to the Plague and Other Infectious Distempers
Bradley, Richard
345 Gutenberg downloadsen2019Difficulty 63 (Academic)
Het Leven der Dieren: Deel 1, Hoofdstuk 02: De Halfapen; Hoofdstuk 03: De Vleermuizen
Brehm, Alfred Edmund
344 Gutenberg downloadsnl2005
Notes on Veterinary Anatomy
Korinek, Charles James
342 Gutenberg downloadsen2019Difficulty 53 (Graduate)
Observations on the Oleum Jecoris Aselli, or Cod-liver Oil Its nature, properties, mode of preparation, &c.
Savory, John
341 Gutenberg downloadsen2021Difficulty 70 (Academic)
Report on the Migration of Birds in the Autumn of 1879. [First Report]
Harvie-Brown, J. A. (John Alexander) & Cordeaux, John
341 Gutenberg downloadsen2021Difficulty 40 (High School)
Sir William Flower
Lydekker, Richard
341 Gutenberg downloadsen2025Difficulty 72 (Expert)
George Washington Carver National Monument Junior Ranger Activity Book: The Scientist
United States. National Park Service
340 Gutenberg downloadsen2020Difficulty 49 (College)
Meeresfische
Floericke, Kurt
339 Gutenberg downloadsde2018
Polarforskningen
Nathorst, A. G. (Alfred Gabriel)
339 Gutenberg downloadssv2009
The O. S. U. Naturalist, Vol. 1, No. 2, December, 1900
Ohio State University. Biological Club
339 Gutenberg downloadsen2023Difficulty 52 (Graduate)
Het Leven der Dieren: Deel 2, Hoofdstuk 11 tot 14: Hoenderkoeten; Nandoes; Kasuarisvogels; Struisen; Hagedisvogels
Brehm, Alfred Edmund
338 Gutenberg downloadsnl2012
The Ohio Naturalist, Vol. II, No. 1, November, 1901
Ohio State University. Biological Club
338 Gutenberg downloadsen2023Difficulty 53 (Graduate)
Notizie del pubblico giardino de' semplici di Padova compilate intorno l'anno 1771
Marsili, Giovanni
336 Gutenberg downloadsit2005
Type specimens of amphibians and reptiles in the Museum of Natural History, the University of Kansas
Duellman, William Edward & Berg, Barbara
336 Gutenberg downloadsen2024Difficulty 56 (Graduate)
Het Leven der Dieren, Deel 3, Hoofdstuk 04: De Insecten
Brehm, Alfred Edmund
334 Gutenberg downloadsnl2020
The American Bee Journal, Volume VI, Number 3, September 1870
Various
334 Gutenberg downloadsen2018Difficulty 56 (Graduate)
Dairy Disagreeables Busy the Bacteriologists
Hall, Frank H. (Frank Henry) & Harding, Harry Alexis & Rogers, L. A. (Lore Alford) & Smith, George A.
331 Gutenberg downloadsen2022Difficulty 56 (Graduate)
The run
Hay, John
331 Gutenberg downloadsen2025Difficulty 48 (College)
The Kansas University Science Bulletin (Vol. I, No. 1)
Various
330 Gutenberg downloadsen2017Difficulty 50 (College)
Suomen maan Meripedot: maalikuvilla selitetyt
Eurén, Gustaf Erik
329 Gutenberg downloadsfi2005
Researches on the Visual Organs of the Trilobites
Lindström, Gustaf
328 Gutenberg downloadsen2022Difficulty 54 (Graduate)
The Preparation of Bees for Outdoor Wintering
Phillips, Everett Franklin & Demuth, Geo. S. (George S.)
328 Gutenberg downloadsen2019Difficulty 53 (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
326 Gutenberg downloadsfr2024
The preparation & mounting of microscopic objects
Davies, Thomas
326 Gutenberg downloadsen2019Difficulty 53 (Graduate)
Case of Filaria loa
Robertson, Douglas Argyll
323 Gutenberg downloadsen2023Difficulty 50 (College)
Which Shall Live—Men or Animals?
Baynes, Ernest Harold
323 Gutenberg downloadsen2021Difficulty 61 (Academic)
Muistelmia hyönteismaailmasta: Kuvauksia hyönteisten tavoista ja vaistosta
Fabre, Jean-Henri
320 Gutenberg downloadsfi2021
The Underworld of Oregon Caves National Monument
Contor, Roger J.
319 Gutenberg downloadsen2019Difficulty 56 (Graduate)
Het Leven der Dieren: Hoofdstuk 8: De Vinduikers; Hoofdstuk 9: de Stormvogels
Brehm, Alfred Edmund
316 Gutenberg downloadsnl2010
Notes on Diseases of Swine, Sheep, Poultry and the Dog Cause, Symptoms and Treatments
Korinek, Charles James
316 Gutenberg downloadsen2019Difficulty 55 (Graduate)
Het Leven der Dieren: Deel 3.8, De Stekelhuidigen, Plantdieren en Sponsen
Brehm, Alfred Edmund
315 Gutenberg downloadsnl2020
The Periodical Cicada, "the 17-year Locust"
United States. Department of Agriculture
315 Gutenberg downloadsen2019Difficulty 51 (Graduate)
The little book of British quadrupeds
May, W.
309 Gutenberg downloadsen2024Difficulty 44 (College)
The Ohio Naturalist, vol. II, no. 2, December, 1901
Ohio State University. Biological Club
309 Gutenberg downloadsen2023Difficulty 64 (Academic)
Antony van Leeuwenhoek, de ontdekker der infusorien, 1675-1875
Haaxman, P. J.
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Notes on Diseases of Cattle: Cause, Symptoms and Treatment
Korinek, Charles James
307 Gutenberg downloadsen2019Difficulty 55 (Graduate)
The Nautilus. Vol. XXXI, No. 2, October 1917 A Quarterly Journal Devoted to the Interests of Conchologists
Various
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Behring, Emil von
307 Gutenberg downloadsen2023Difficulty 67 (Academic)
La flore utile du bassin de la Gambie
Rançon, A. (André)
304 Gutenberg downloadsfr2024
A synopsis of the palms of Puerto Rico
Cook, O. F. (Orator Fuller)
303 Gutenberg downloadsen2023Difficulty 63 (Academic)
Az ember helye a természetben
Lenhossék, Mihály
302 Gutenberg downloadshu2024
Het Leven der Dieren, Deel 3, Hoofdstuk 5: De Spinachtigen
Brehm, Alfred Edmund
302 Gutenberg downloadsnl2020
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Coe, H. S. & Martin, John N. (John Nathan)
299 Gutenberg downloadsen2020Difficulty 60 (Graduate)
The Florist and Horticultural Journal, Vol. II. No. 7, July, 1853 A Monthly Magazine of Horticulture, Agriculture, Botany, Agricultural Chemistry, Entomology, &c.
Various
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Use of the Dead to the Living
Smith, Southwood
299 Gutenberg downloadsen2018Difficulty 67 (Academic)
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)
298 Gutenberg downloadsen2021Difficulty 63 (Academic)
Mushroom and Toadstools How to Distinguish Easily the Differences Between Edible and Poisonous Fungi
Smith, Worthington George
295 Gutenberg downloadsen2019Difficulty 49 (College)
Rodent Control Aided by Emergency Conservation Work
Young, Stanley Paul
295 Gutenberg downloadsen2019Difficulty 64 (Academic)
The American Apiculturist. Vol. III. No. 6, June 15, 1885 A Journal Devoted to Scientific and Practical Beekeeping
Various
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Provincial Board of Health of Ontario
292 Gutenberg downloadsen2019Difficulty 68 (Academic)
Het Leven der Dieren: Deel 3.9, De Oerdieren
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291 Gutenberg downloadsnl2021
Wintering Bees in Cellars
Phillips, Everett Franklin & Demuth, Geo. S. (George S.)
290 Gutenberg downloadsen2019Difficulty 52 (Graduate)
An inaugural dissertation on pulmonary consumption
Delafield, Edward
289 Gutenberg downloadsen2022Difficulty 63 (Academic)
Powder-Post Beetles in Buildings: What to Do About Them
St. George, R. A. (Raymond Alexander) & McIntyre, T.
287 Gutenberg downloadsen2019Difficulty 50 (College)
Reprint of Two Tracts 1. An essay on gleets. 2. An enquiry into the nature, cause, and cure of a singular disease of the eyes
Marat, Jean Paul
287 Gutenberg downloadsen2018Difficulty 56 (Graduate)
Die Protozoen als Krankheitserreger des Menschen und der Hausthiere Für Ärzte, Thierärzte und Zoologen
Schneidemühl, Georg
285 Gutenberg downloadsde2016
The Ornithologist and Oölogist. Vol. VIII No. 3, March 1883 Birds: Their Nests and Eggs
Various
282 Gutenberg downloadsen2019Difficulty 42 (College)
House Flies
Howard, L. O. (Leland Ossian)
266 Gutenberg downloadsen2019Difficulty 56 (Graduate)
Das Protoplasma der Rhizopoden und der Pflanzenzellen ein Beitrag zur Theorie der Zelle
Schultze, Max
263 Gutenberg downloadsde2022
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Pascal, Teodoro
255 Gutenberg downloadsit2019
How Does a Tree Grow? Or, Botany for Young Australians
Bonwick, James
254 Gutenberg downloadsen2018Difficulty 34 (High School)
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Pascal, Teodoro
246 Gutenberg downloadsit2018
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Zell, Th. (Theodor)
241 Gutenberg downloadsde2025
The Canadian Entomologist, Vol. XII., No. 2, February 1880
Various
241 Gutenberg downloadsen2018Difficulty 47 (College)
A Letter on Suspended Animation containing experiments shewing that it may be safely employed during operations on animals
Hickman, Henry Hill
239 Gutenberg downloadsen2018Difficulty 77 (Expert)
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Hérincq, F. (François)
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Grasset, J. (Joseph)
227 Gutenberg downloadsfr2019
The Fern Bulletin, October 1903 A Quarterly Devoted to Ferns
Various
214 Gutenberg downloadsen2018Difficulty 50 (College)

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

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

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

Life and Letters of Charles Darwin — Volume 1

The Notebooks of Leonardo Da Vinci — Complete

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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

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

Origin of Cultivated Plants The International Scientific Series Volume XLVIII

The Descent of Man, and Selection in Relation to Sex

The Voyage of the Beagle

Grundzüge der Paläontologie (Paläozoologie). 1. Abteilung: Invertebrata.

Micrographia Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses with Observations and Inquiries Thereupon

Flora von Deutschland Ein Hilfsbuch zum Bestimmen der zwischen den deutschen Meeren und den Alpen wildwachsenden und angebauten Pflanzen

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On Growth and Form

The Evolution of Man

Identification of the Larger Fungi

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

Form and Function: A Contribution to the History of Animal Morphology

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

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

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

Letters of Asa Gray; Vol. 2

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

The Autobiography of Charles Darwin

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Explanation of Terms Used in Entomology

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Mutual Aid: A Factor of Evolution

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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.

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

An introduction to the study of mammals living and extinct

Aristotle's History of Animals In Ten Books

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Vestiges of the Natural History of Creation

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

The Formation of Vegetable Mould Through the Action of Worms With Observations on Their Habits

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

The Bird Book Illustrating in natural colors more than seven hundred North American birds; also several hundred photographs of their nests and eggs.

Studies in the History and Method of Science, vol. 1 (of 2)

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

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.

Identifying Hardwoods Growing on Pine Sites

The Power of Movement in Plants

The Descent of Man and Selection in Relation to Sex, Vol. I

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

The Science of Fingerprints: Classification and Uses

Evidence as to Man's Place in Nature

Reptiles and Birds A Popular Account of Their Various Orders, With a Description of the Habits and Economy of the Most Interesting

The Variation of Animals and Plants Under Domestication, Volume II (of 2)

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

A History of North American Birds; Land Birds; Vol. 1 of 3

The Biotic Associations of Cockroaches

Galen: On the Natural Faculties

The Variation of Animals and Plants under Domestication

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