8 Preface 



terial, we begin with a study of the vertebrates. While it may appear 

 more logical to start with the protozoans, we have found in practice 

 that it is better for us to start with the vertebrate. Many of our students 

 have had little or no acquaintance with the smaller animals, but have 

 at least an elementary knowledge of the general anatomy of the verte- 

 brates. Further, they are interested in the group of animals to which 

 they belong. Working from the partially known and already interest- 

 ing vertebrates, we excite their interest still more and are, in most in- 

 stances, able to retain it throughout the course. Following the study 

 of vertebrate anatomy and physiology, we return to the cell, make a care- 

 ful study of it, and from this, logically build up to embryology, genetics, 

 and evolution. Next we make a survey of the animal kingdom, unifying 

 the many diverse forms by concepts of phylogeny. In this portion we 

 study type forms and stress their biological and economic importance. 

 Finally we close the course with a discussion of ecology which incor- 

 porates the many facts and ideas previously discussed. 



Although this adds another book to an already large list, we be- 

 lieve we have contributed something new to the teaching of zoology. 

 We have tried to incorporate newer ideas and concepts without sacri- 

 ficing basic anatomy, classification, or phylogeny. Also we have tried 

 to present a book which is not so large that it will frighten the timid 

 freshman. 



Naturally the book follows the sequence of our course at Pur- 

 due ; however, for those who find other sequences more successful for 

 their particular classes, we have arranged the sections in such a man- 

 ner that it is possible to begin with any one. 



We would like to thank several persons who have aided mate- 

 rially in the preparation of the manuscript. The many colleagues and 

 assistants who have worked in our general zoology course have con- 

 tributed ideas and suggestions in developing the course. Many of these 

 suggestions have been incorporated in this book. We would especially 

 like to thank Dr. Fred Kamemoto and Mr. Kenneth Hutton who have 

 read portions of the manuscript and contributed suggestions, and Dr. 

 A. E. H. Gaumer who has not only offered valuable advice, but has 

 also labeled the drawings and made several charts. 



The drawings were largely the work of one of the authors (Marie 

 Goodnight). A number of them, including those of the frog and of 

 the animal groups, were done by Mrs. Lucille Bertram. Her ability has 

 contributed much to those illustrations. The drawings which were 

 generously lent by other publishers have been acknowledged under the 

 illustration concerned. 



Clarence J. Goodnight 

 Marie L. Goodnight 



Lafayette, Indiana. 



