“The present work consists of twenty-eight lectures arranged in six groups. The first lecture is an introduction dealing with ‘Theories of evolution’ and ‘Methods of investigation.’ ... The second division of lectures (II.-IV.) deals with ‘Elementary species in nature.’ ... In lectures V.-XV., the author presents the evidence to show that ‘varieties’ are produced either by the loss of some marked peculiarity, or by latent characters becoming active, or by the acquisition of others that are already present in allied species.... Lectures XVI.-XXIV. Although the author tested many species, only one, the evening primrose, Œnothera, gave positive, mutating, results. He finds that the various mutations obtained from this species take place with a great degree of regularity. Very simple rules of general validity, he assumes, govern the whole phenomenon.... Lectures XXV.-XXVIII. There is selection of two kinds, between species and between varieties.”—Philos. R.
“‘Species and varieties,’ then, within the field of natural science, is clearly the book of the year. On the practical side it gives unity and significance to the random observations of every lover of plants. On the theoretical side, the work articulates with Mendel’s old doctrine of the unit character, the heredity atom which either is, or is not, and never splits in passing from one generation to the next.” E. T. Brewster.
| + + + | Atlan. 96: 683. N. ‘05. 850w. |
“‘The greatest contribution since Darwin’ is the universal testimony.” H. C. Cowles.
| + + + | Bot. G. 40: 148. Ag. ‘05. 900w. | |
| + + + | Ind. 58: 1187. My. 25, ‘05. 810w. |
“The book is, considering its bulk, very free from misprints.” A. D.
| + + + | Nature. 72: 314. Ag. 3, ‘05. 1560w. | |
| + + | Outlook. 79: 605. Mr. 4, ‘05. 100w. |
“Evidently the work of de Vries may well prove to be an epoch-making contribution to the advance of knowledge.” Edward G. Spaulding.
| + + | Philos. R. 14: 354. My. ‘05. 2760w. | |
| + + | Pub. Opin. 38: 344. Mr. 4, ‘05. 970w. |
“The great service of de Vries’s work is that, being founded on experimentation, it challenges to experimentation as the only judge of its merits. As to the literary qualities of the book, one has first to praise the general method of exposition. It is quite a model.” C. B. Davenport.