INTRODUCTION g 



Comparative anatomy becomes a large part of the study 

 of every form, as each additional animal furnishes a new 

 solution to an old problem. Materials are thus accumulated 

 and the points of structure of greatest value are clustered 

 around the life problems as apperceptive bases. 



Classification is the natural outgrowth of comparative 

 anatomy and is given considerable emphasis. The author 

 believes that this has been too much neglected in recent 

 years and that the time has come to reinstate it in a rational 

 way in the courses in Zoology. But the required work in 

 classification should consist of an arrangement of the com- 

 parisons made from laboratory and field study and need not 

 at this stage include the technicalities of the specialist. 

 However, the use of the manuals of insects and birds may 

 be taught so that students can pursue these delightful stu- 

 dies further if they so desire. 



Collections of insects can be made with very little efifort 

 and most students at this age are inclined to make them. 

 Such collections, besides the disciplinary value which is 

 great, have a very great value as illustrations of variation 

 and adaptation, the two things which have been prominently 

 associated throughout the work. The laboratory should 

 if possible contain a working collection of insects and birds 

 at least, so that the students may use them in comparing 

 and classifying their own specimens. 



This book is not intended to take the place of the teacher, 

 but rather to awaken an appreciation and a demand for the 

 teacher's best efifort. It is insisted that the teacher tell the 

 student as little as possible about the things which he can 

 discover for himself, but through all this work the teacher 

 is the guiding spirit and should give to it his most earnest 



