138 The Unity of the Organism 



particular issue here, it will be noticed, is the vitally im- 

 portant one of what might be called the functional as 

 distinguished from the hereditary cause or at least incitement 

 of growth. 



In illustration of the importance of understanding the 

 unification among these complex systems, the manifestation 

 of which is in turn dependent upon the organism as a whole, 

 the following from the address by L. F. Barker already re- 

 ferred to, is impressive. 



"In how far these sudden and violent excitations of the 

 autonomic nervous system which accompany strong emo- 

 tions are due to the intervention of the glands of internal 

 secretion, and in how far they depend upon direct neural 

 conduction from the brain, we are as yet but ill-informed. I 

 need only remind you of the vasodilation of the face in the 

 blush of shame, of the palpitation of the heart in joy, of the 

 stimulation of the sudoriparous glands which precedes the 

 sweat of anxiety, of the stimulation of the vasoconstrictors, 

 the pupil dilators and the pilomotors in the pallor, mydriasis 

 and goose-skin of fright, to illustrate some of these violent 

 autonomic excitations." ^^ 



The references here, it will be noted, are primarily mani- 

 festations pertaining to the surface, the integumentary 

 parts of the body, and their scope is what especially inter- 

 ests us. Very nearly the whole list of these parts is in- 

 volved, and probably a complete inventory would be still 

 more inclusive. 



Now notice the range of manifestations at a deeper level 

 that are involved. "The balance maintained normally be- 

 tween the two antagonistic systems the vagal and sympa- 

 thetic autonomic is one of the most interesting of physio- 

 logical phenomena. Think, for example, of the rate of the 

 heart-beat — how constantly it is maintained at a given level 

 in each individual when the body is at rest ; the impulses ar- 

 riving through the vagal system just balance those arriving 



