PREFACE 



THIS book is intended for the use of students in secondary 

 schools. It includes sufficient material for an entire year's 

 work, but certain chapters or parts of chapters may be elimi- 

 nated if less time is available. The large number of chapters 

 and their short length make elimination easy and also facilitate 

 the assignment of lessons. For example, the book may be 

 adapted for a half year course by omitting chapters III, XII, 

 XIV, XVI-XVIII, XX-XXIV, XXVIII, XXX, XXXV, and 

 XXXIX. The word " practical " in the title has been chosen 

 since an effort has been made to present those facts and theories 

 about animals which will have the most practical bearing upon 

 the daily life of the student. It refers not alone to the eco- 

 nomic side of the subject but also to the elements that are of 

 greatest intellectual value. 



Ideas differ considerably as to what constitutes the best course 

 in zoology for secondary schools, but we cannot be far wrong if 

 we succeed in combining a general knowledge of animals and 

 of zoological principles with a discussion of the relations of 

 animals to man, in such a way as to interest the students. The 

 constant references to the relations of animals to their environ- 

 ment and the selection of common animals, especially those of 

 economic importance, for illustrative purposes tend to stimulate 

 the natural interest of boys and girls in animal life. 



Many of the illustrations are from photographs which show 

 the living animals in their natural environment. Next to the 

 animals themselves, photographs of this kind furnish the best 

 idea of the species studied. The drawings representing ana- 

 tomical structures have been selected so as not to duplicate 

 those called for in the laboratory manual. 



