PREFACE 7 



are unable to carry on the laboratory work on the same 

 animals with the same degree of thoroughness. Those 

 who are unable to secure any material for study will find 

 in the illustrations excellent substitutes, but it is hoped 

 that every teacher will strive to afford his pupils that 

 mental stimulus and specially valuable mind culture re- 

 sulting from a face to face acquaintance with animal life. 

 At best, it is impossible to secure all the material necessary 

 to demonstrate the ideas to be taught, and therefore 

 numerous illustrations have been introduced. Much time 

 and expense have been given to the preparation of the 

 photographs, which can be relied on as representing facts 

 more accurately than drawings, and approaching as nearly 

 as possible to nature itself. 



The subject matter has been so treated as to adapt the 

 book to schools giving either a half or whole year to the 

 study of zoology. Those preferring it can begin the study 

 with the Protozoa and proceed to the higher forms, instead 

 of following the order given in the text, as the chapters in 

 Parts I and II are so written as to be largely independent 

 of each other. Teachers having only a half year for 

 Zoology will perhaps find it wise to omit certain chapters 

 in order that the time which ought to be spent in studying 

 the animals shall not be devoted to the study of the 

 book. It is not expected that most schools will be able 

 to give careful attention to all the subjects treated, but 

 the numerous forms and phases of animal life have been 

 presented in order to allow some choice on the part of 

 the teacher desiring to emphasize special features of 

 zoological study. 



Mr. D, S, Hartline, of the State Normal School at Blooms- 



