48 STUDIES IN ADVANCED PHYSIOLOGY. 



CLASSIFICATION. 



When all of these data concerning any living thing are 

 known we have the information at hand to properly classify 

 it in the grand system of nature, and to determine in what 

 group or family it finds its natural place. 



A mere glance at the human body reveals a multiplicity 

 of structures, all, however, co-ordinated to one general pur- 

 pose. Thus, we have the system of the supporting tissues, 

 which preserve the form and sustain the weight of the 

 body ; a complicated system of muscles used in performing 

 our movements ; a generally distributed nervous system to 

 exercise a controlling influence, and so on through the many 

 instances which might be here adduced. For arbitrary 

 rather than natural reasons the discussion of human physi- 

 ology is here divided into the following chapters, each of 

 which seeks to treat in detail of some particular system of 

 the body. 



