TWENTIETH CENTURY TEXT-BOOKS. 



TEXT-BOOKS OF ZOOLOGY. 



By David Starr Jordan, President of Leland Stan- 

 ford Xr. University; Vernon Lyman Kellogg, Professor 

 of Entomology ; Harold Heath, Assistant Professor of 

 Invertebrate Zoology; and George C. Price, Associate 

 Professor of Zoology in Leland Stanford Jr. University. 



Animal Studies. 



A compact but complete treatment of elementary zoology, especially 

 prepared for institutions of learning tliat prefer to find in a single book 

 an ecological as well as morphological survey of the animal world. l2mo. 

 Cloth, $1.25. 



Anima] Life. 



An elementary account of animal ecology — that is, of the relations 

 of animals to their surroundings. It treats of animals from the stand- 

 point of the observer, and shows why the present conditions and habits 

 of animal life are as we find them. It explains how the infinite variety 

 of form and nature is the inevitable outcome of the struggle for existence. 

 l2mo. Cloth, $1.20. 



Animal Forms. 



This book deals in an elementary way with animal morphology. It 

 describes the structure and life processes of animals, from the lowest, 

 simplest, one-celled creations to the highest and most complex, discussing 

 therewith the important subject of division of labor. i2mo. Cloth, $1.10, 



Ai^imals. 



This consists of "Animal Life " and "Animal Forms" bound in one 

 volume, and groups the entire body of material needed for an elementary 

 course in zoology in a handy and compact volume. l2mo. Cloth, $1.80, 



m 



Animal Structures. 



A laboratory guide in the teaching of elementary zoology. l2mo. 

 Cloth, 50 cents. 



D. APPLETON AND COMPANY, 

 MEW YORK. BOSTON. CHICAGO. LONDON 



