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RECENT BOOKS 



Animal Communities in Temperate America. 



By Victor E. Shelford, Instructor in Zoology in the University of Chicago. 



This volume by Dr. Shelford presents the principles of field ecology, illustrated by the more widely distribtited 

 animal habitats of the eastern half of temperate North America, and the aquatic habitats of a much larger territory. 

 Six chapters deal with general principles. 



In several chapters the ammal communities of lakes, streams, swamps, forests, prairies, and various soils and topo- 

 graphic situations are considered from the point of view of modern dynamic ecology. A very valuable feature of the book 

 is the three hundred figures of widely distributed animals chosen to represent the chief types of animal communities 

 and their characteristic modes of life. 



380 pages, 8vo, cloth; price S3.00 (weight 44 oz.). 



Artificial Parthenogenesis and Fertilization. 



By Jacques Loeb, Member of the Rockefeller Institute for Medical Research. 



This new work presents the first complete treatment of the subject of artificial parthenogenesis in English. Pro- 

 fessor Loeb published four years ago a book in German \mder the title Die chemische Entwicklungaerregung des tieri- 

 Bchen Eies. Mr. W. O. R. King, of the University of Leeds, England, translated the book into English, and the trans- 

 lation has been revised, enlarged, and brought up to date by Professor Loeb. It gives, as the author says in the pre- 

 face, an accoimt of the varioiis methods by which unfertilized eggs can be caused to develop by physico-chemical 

 means, and the conclusions which can be drawn from them concerning the mechanism by which the spermatozoon in- 

 duces development. Since the problem of fertihzation is intimately connected with so many different problems of physi- 

 ology and pathology, the be suing of the facts recorded and discussed in the book goes beyond ftithe special problem 

 indicated.by the title. 



t31S pages, 12mo, cloth; price $2.50 (weight 36 oz.). ] 



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