AUTHOR'S PREFACE. 



This book is intended primarily for students who have 

 had little previous knowledge of insects, or animals of any 

 sort. The animals chosen for discussion have been the 

 more familiar ones which live with us from day to day. 

 Two modes of approach to the subjects of study are in- 

 tended : the investigative study of the animals themselves, 

 as provided for in the directions for field work with the 

 different groups of animals ; and the class discussions of the 

 facts observed, in their bearing upon each other and upon 

 the many problems which living beings are continually 

 offering for our solution. In the latter phase of study 

 the teacher must be a large factor. One cannot put into 

 a text-book all there is in a subject The present form of 

 the book is the outcome of its progressive use in the 

 school-room, and thus has, at least, the merit of having 

 been tried. 



The method of presentation of the subject is based 

 upon two lines of belief : first, that life is one of the inost 

 interesting facts of creation, if not the most interesting; 

 and, second, that life is a continuous fact, of common 

 powers but various in its expression, whether one proceeds 

 from the simple to the complex, from the early to the late, 

 or from the low to the high. These are facts that are 

 usually reserved for the student who has already acquired 

 some body of knowledge of animal Hfe; but younger stu- 

 dents, beginners, find quite as much delight and profit 



