An Introduction to Zoology 



By 

 ROBERT W. HEGNER, Ph.D. 



Instructor in Zoology in the University of Michigan 



Illustrated, 12mo, $1.90 net 



Only a few animals belonging to the more important phyla, as viewed 

 from an evolutionary standpoint, are considered. They are, however, inten- 

 sively studied in an endeavor to teach the fundamental principles of Zoology 

 in a way that is not possible when a superficial examination of types from 

 all the phyla is made. Furthermore, morphology is not specially empha- 

 sized, but is coordinated with physiology, ecology, and behavior, and serves 

 to illustrate by a comparative study the probable course of evolution. The 

 animals are not treated as inert objects for dissection, but as living organ- 

 isms whose activities are of fundamental importance. No arguments are 

 necessary to justify the " type course," developed with the problems of or- 

 ganic evolution in mind, and dealing with dynamic as well as static phe- 

 nomena. 



" I have read your chapter (The Crayfish and Arthropods in Gen- 

 eral) and can express my satisfaction with reference to the general 

 arrangement of the matter, as well as with reference to the detail. 

 The whole treatment is up to date, taking account of the modern ad- 

 vancement in our knowledge of the crayfishes, and, chief of all, the 

 more important features in the natural history of these animals are 

 very properly separated from the unimportant ones. I think this 

 chapter gives the essence of what we know about crayfishes, and any 

 student might use the book advantageously. In fact, I know no other 

 text-book which gives such a wealth of information upon so few 

 pages." Professor A. E. ORTHMANN, Carnegie Museum. 



" The plan is very satisfactory, and the book will be very instructive 

 for class use. I am very glad that you have chosen the bee as your 

 insect type." (Chapter XII.) Dr. E. E. PHILLIPS, Department of 

 Agriculture, Washington, D.C. 



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