Structure and Function. 7^ 



they have in arranging the fibers of the Oak or the 

 angle of its branches with the trunk. 



We now wish especially to call attention to the 

 instinct-like operations of vitality in building up 

 individual structures— arranging all their parts and 

 bringing them into harmonious action. 



The function of an organ is often what it is, or 

 rather becomes useful to the being on account of 

 the structure of the organ itself or of some part 

 connected with it. Of what use would be the func- 

 tion of the stomach for secreting gastric juice, were 

 the stomach not connected with an apparatus for 

 supplying it with food and also with other organs 

 for the distribution of the nutriment to different 

 parts of the body? What benefit the synovial fluid, 

 if there were no joint to be lubricated by it ? 



We see structure and function within the ani- 

 mal body producing certain results for the body it- 

 self and for the species. In plants, and some of the 

 lowest forms of animals perhaps, the work is com- 

 pleted by these two agencies alone. But when any 

 being is of so high a type that structure and func- 

 tion alone cannot complete the work, then we find 

 Instinct added to act as the handmaid of these two 

 primitive workers, to supply materials or to give a 

 wider range of activities, and finally to bring enjoy- 

 ment to the individual through its activities. We 

 find Structure, Function, and Instinct in its lowest 

 form, all working together in the same line, appar- 

 ently for the same purpose, or if for different sim- 

 ple, subordinate purposes, to secure the same com- 

 plex end. The most careful study of these three 



