TJNIFOEMITIES AND COMPAEISONS AMONG COMPONENTS 399 



wildering miscellany the material becomes ordered and useful. 

 Considered in this way all that has been presented may be viewed 

 as requisite to comprehensions of organisms. Thereupon it be- 

 comes possible to derive general statements concerning what organ- 

 isms do to maintain their constant properties. 



It is clear that regulations have to do with what I have defined 

 as contents (properties) of the organism. Content of each com- 

 ponent varies within the limits fixed by the processes of its mainte- 

 nance. Departures from this norm are forestalled by behaviors 

 whereby the animal frequents environments that favor the norm, 

 and by compensations whereby exchanges are modified in a direc- 

 tion to restore the norm. Some processes are ready at all times to 

 prevent or to correct departures of every component. A separate 

 structure is not available for performing each such duty. All the 

 processes have patterns that are similar in many features that have 

 been mentioned ; in addition each exhibits quantitative differences 

 peculiar to it. The species is physiologically characterized by that 

 particular combination of these quantitative features which it 

 embodies. 



