598 THE POSTERIOR PITUITARY AND THE NERVOUS SYSTEM. 



ground for the conclusion that the posterior pituitary body is 

 the center from which the impulses that incite and govern the func- 

 tional activities of the general motor system originate. 



The relationship that exists between the cranial nerves and 

 the posterior pituitary body now becomes apparent. Not only 

 do the ten nerves endowed with motor properties either in toto 

 or in part owe their functional impulses to this body, but those 

 which regulate their functional blood-supply also. Again, as 

 all organs require functional impulses and blood, and inasmuch 

 as these impulses and the blood must be incited and governed, 

 all organs must be functionally dominated by the posterior 

 pituitary body. Indeed, all the data that we have presented in 

 this work tend to show that the posterior pituitary body is the 

 chief motor center of the organism; it incites and governs the 

 functional activity of all organs, including the vascular system 

 and, through the latter, the brain. 



The anatomical relations of the posterior pituitary are 

 shown in the annexed colored plate prepared by us to portray 

 the relationship between this organ, the floor of the third ven- 

 tricle, the medulla, the pons, and the cord all of which struct- 

 ures are continuous. 



THE POSTERIOR PITUITARY AS THE CENTRAL SENSORIUM. 



From all the data submitted and the normal functional 

 association embodied in reflex phenomena manifested through 

 various nerves the vagus, for example motor-efferent phe- 

 nomena are the normal sequences of sensory-afferent impres- 

 sions, and the two are necessarily linked. The pons Varolii, or 

 at least its gray ganglionic substance, is now thought to originate 

 motor impulses that are independent of mental processes and 

 to be the seat of instinctive acts. "It is, indeed, to the pons," 

 says Professor Duval, "that, in a general way, we appear au- 

 thorized to ascribe the most important role in great emotional 

 expressions: laughing, weeping, the cry of pain; in a word, in- 

 voluntary manifestations. It is in this sense that the term 

 sensorium commune applied to the pons should be understood. 

 Indeed, if, as was done by Vulpian, the corpora striata, the optic 

 thalami, the tubercula quadrigemina, and the cerebellum are 



M The hemispheres had doubtless been previously removed. 



