SERIES OF MOVEMENTS AND TROPHIC ACTIONS. 279 



sion of movements may be highly expressive. 

 When we see a child turn his head towards an 

 apple, extend his shoulder and elbow, then flex 

 wrist and fingers till they grasp the apple, we 

 observe a succession of movements expressing to 

 us that the child sees the apple, and desires to 

 have it; the expression is a series or succession 

 of movements. When we compare the body of 

 an infant one year old with a child aged three, 

 the difference of their bodies in size, weight, pro- 

 portional development, etc., indicates or expresses 

 the difference of age. Some modes of expression 

 are by kinetic function in the subject, others by its 

 trophic functions. The expressive movements de- 

 scribed in the child taking the apple are its kinetic 

 functions; the points of difference between the 

 body of the infant and the older child are its 

 trophic manifestations. 



Now, most of our biological works deal mainly 

 with the description of the material presence of the 

 subject, i.e. its trophic functions. Say the subject 

 of the biologist's description is the growth of the 

 common bean. The seed swells, each cotyledon 

 enlarges, the radicle of the embryo elongates by 

 growth, and protrudes from the opening in the 

 seed covering called the micropyle. Then the 

 covering is burst, the plumule protrudes, its hypo- 

 cotyls bend towards the light, the leaflets of the 

 plumule open out, etc. If carefully analyzed, the 

 process of development .described briefly will be 

 found to consist of the enumeration of a series of 

 trophic and kinetic actions of the parts of the sub- 



