Herrick, Nerve Components of Bony Fishes. i^j 



Section i. — Introductory. 



I. — General Introduction. 



Looked at from the biological standpoint, the primary 

 function of the nervous system is to put the organism 

 into relation with the outer world, the external environ- 

 ment. The health of the body is largely determined, 

 in last analysis, by the perfection of the correspondence 

 between the inner activities and the forces of nature 

 outside. 



The immediate mechanism upon which this correspond- 

 ence directly depends — the sense organs and peripheral 

 nervous system — must not be overlooked by the neurolo- 

 gist who would thoroughly understand the normal or 

 pathological processes of the nervous system as a whole. 

 Even the higher psychic processes in the central nervous 

 system cannot be thoroughly understood without the 

 knowledge of the peripheral nervous system. This is 

 clearly understood by the psychologists who recognize that 

 psychic phenomena cannot be studied without reference 

 to their physiological concomitants, which in turn requires 

 investigation into the morphology of the nervous system 

 both peripheral and central. 



It is unnecessary at this late day to urge the importance 

 to normal physiology (and not less to pathology) of a true 

 morphological comprehension of the structure that reacts 

 to stimuli of the external environment. This implies a 

 broad philosophical appreciation of the relations between 

 part and part; of the functional, mechanical and other 



