| Aristotle, Historia Animalium, translated by D’Arcy Wentworth Thompson. | Historia Animalium. |
| Castle, W. E., Genetics and Eugenics. | Genetics and Eugenics. |
| Conklin, Edwin Grant, The Direction of Human Evolution. | Evolution. |
| Darwin, Emma, A Century of Family Letters, two volumes. | Family Letters. |
| Darwin, The Life and Letters of Charles Darwin, two volumes. | Life. |
| De Vries, Hugo, Species and Varieties, Their Origin by Mutation. | Species and Varieties. |
| Goncourts, Edmond et Jules, Journal des Goncourts, nine volumes. | Goncourts, Journal. |
| Gray, Asa, Letters of, edited by Jane Loring Gray, two volumes. | Gray Letters. |
| Grant Duff, Sir Mountstuart E., Notes from a Diary, fourteen volumes, 1851-1901. | Grant Duff. |
| Huxley, Thomas H., Darwiniana (the second volume of Collected Essays). | Darwiniana. |
| Huxley, Thomas H., Life and Letters of, by his son Leonard, two volumes. | Huxley, Life. |
| Lull Richard, Harry Burr Ferris, George Howard Parker, James Rowland Angell, Albert Galloway Keller, Edwin Grant Conklin, The Evolution of Man. | Lull. |
| Morgan, Thomas Hunt, Evolution and Adaptation. | Evolution and Adaptation. |
| Osborn, Henry Fairfield, The Earth Speaks to Bryan. | The Earth Speaks. |
| Osborn, From the Greeks to Darwin. | Greeks to Darwin. |
| Osborn, Henry Fairfield, Impressions of Great Naturalists. | Great Naturalists. |
| Parker, George Howard, What Evolution Is. | What Evolution Is. |
| Pearson, Karl, The Grammar of Science. | Grammar of Science. |
| Thoreau, Henry, Journal, fourteen volumes. | Journal. |
| Vallery-Radot, Pasteur. | Vallery-Radot, Pasteur. |
| Wallace, Alfred Russell, My Life, two volumes. | Wallace, Life. |
| Whitehead, Alfred North, Science and the Modern World. | Science and the Modern World. |