Books in Biology (sorted by popularity)
- Lamarck, the Founder of Evolution: His Life and Work A. S. Packard 143 downloads
- Darwinism (1889) Alfred Russel Wallace 142 downloads
- Life History of the Kangaroo Rat Charles Taylor Vorhies and Walter P. Taylor 139 downloads
- Form and Function: A Contribution to the History of Animal Morphology E. S. Russell 137 downloads
- The Human Side of Animals Royal Dixon 135 downloads
- Ducks at a Distance: A Waterfowl Identification Guide Bob Hines 131 downloads
- Darwin and Modern Science A. C. Seward 131 downloads
- The Story of the Living Machine H. W. Conn 128 downloads
- De l'origine des espèces (French) Charles Darwin 116 downloads
- "Wee Tim'rous Beasties": Studies of Animal life and Character Douglas English 112 downloads
- Text Book of Biology, Part 1: Vertebrata H. G. Wells 112 downloads
- The Minds and Manners of Wild Animals: A Book of Personal Observations William T. Hornaday 112 downloads
- Nouveaux souvenirs entomologiques - Livre II (French) Jean-Henri Fabre 108 downloads
- My Studio Neighbors W. Hamilton Gibson 104 downloads
- On the Reception of the 'Origin of Species' Thomas Henry Huxley 104 downloads
- Nature Near London Richard Jefferies 102 downloads
- The Origin of Species Thomas Henry Huxley 100 downloads
- Evolution, Old & New Samuel Butler 99 downloads
- Souvenirs entomologiques - Livre I (French) Jean-Henri Fabre 97 downloads
- Anecdotes of the Habits and Instinct of Animals Mrs. R. Lee 96 downloads
- Species and Varieties, Their Origin by Mutation Hugo de Vries 95 downloads
- Concerning Animals and Other Matters Edward Hamilton Aitken 95 downloads
- Darwin, and After Darwin, Volumes 1 and 3 George John Romanes 92 downloads
- Ohio Biological Survey, Bull. 10, Vol. 11, No. 6 Bruce Fink and Leafy Jane Corrington Hilker 91 downloads
- Love's Meinie: Three Lectures on Greek and English Birds John Ruskin 91 downloads