134 MOVEMENT IN ANIMALS 



assigned to one or another of these classes. An inter- 

 esting fact is that the specialized activities of civilized 

 men, the activities in which they differ most strikingly 

 from their uncivilized fellows, fall mostly either into class 

 (c), grasping, or class (/), voice production. We realize 

 the truth of this when we consider that all use of tools 

 and instruments, including pens, comes under the 

 head of grasping, and that it is by voice production 

 that all ideas which are not committed to writing are 

 communicated. 



