lOO A GUIDE FOR THE STUDY OF ANIMALS 



1. The Struggle for existence — 

 a. its cause, 



d. its threefold nature, 



c. the various kinds of adaptations. 



2. The various methods of protection from enemies. 

 a. The exoskeleton. 



d. Protective coloration. 



c. Animal associations. 



d. Protective habits. 



e. Defensive structures. 



