INTRODUCTION II 



tain forms or certain parts of the anatomy of several forms. 

 The work on insects, for instance, is so arranged that any 

 insect may be taken first and some of the forms may be 

 omitted entirely or the work reduced so that the necessary 

 time may be saved. It is believed that a reasonably thor- 

 ough study of a few types is better than a superficial study 

 of many types, and that a sympathy with living nature based 

 upon a knowledge of her laws, is of greater importance 

 than a deeper study of anatomy only. 



