The Open Court Biological Series 



HUGO DE VRIES 



Species and Varieties, Their Origin by Mutation, Lectures 

 delivered at the University of California by Hugo 

 de A>ies, Professor of Botany in the University of 

 Amsterdam. Second thoroughly revised and cor- 

 rected edition, with portrait in photogravure. 1906. 

 Pages xviii, 847. Price $5.00 net. (21s. net.) 



It is evident that the new theory of mutations must be recog- 

 nized in all discussions of questions as to origin and develop- 

 ment. For instance, if the empirical view of consciousness be 

 taken, why should it not be quite possible that this has 

 appeared in the phylogenetic development of certain species 

 as a mutation ? And what becomes of those arguments for 

 design which have been based on adaptation by slow accumu- 

 lative changes? Evidently the work of De Vries may well 

 prove to be an epoch making contribution to the advance of 

 knowledge. It makes the study of evolution in part experi- 

 mental, modifies the current views as to origin, selection and 

 adaptation, and finds a place for non-heredity and discon- 

 tinuity, for chance and irregularity. Edward G. Spaulding 

 in The Philosophical Review. 



EDWARD DRINKER COPE 



Among American naturalists Cope takes decidedly a most 

 prominent rank. His numerous original contributions 

 to paleontology, and observations in other lines have 

 been largely accepted by his colleagues, while his in- 

 terpretation of the doctrine of evolution, has been a 

 powerful factor in the formation of modern thought. 



The Primary Factors of Organic Evolution, by the late E. D. 

 Cope, Ph. D., ^Member of the United States National 

 Academy of Sciences : Professor of Zoology and Com- 

 parative Anatomy in the University of Pennsylvania. 

 Second edition. 1904. 121 illustrations. Pp. 550. 

 Tables, bibliography and index. Cloth $2.00 net. 

 (10s.) 



"Will stand as the most concise and complete exposition of 

 the doctrines of the Neo-Lamarckian school hitherto published. 

 A most valuable text-book for teachers and students." 

 Science, N. Y. 



"A work of unusual originality. No one can read the book 

 without admiring the intimate knowledge of facts and the 

 great power of generalization which it discloses." Prof. J. 

 McK. Cattell. 



"K thoughtful and scholarly presentation imencumbered 

 by guesses at facts or reasoning from probabilities." Ameri- 

 can Register, Paris. 



