THE MOVEMENTS OF THE STOMACH 787 



portion augmented peristaltic waves. On the pylorus itself we 

 may obtain from vagal stimulation either increased or diminished 

 contraction. The conditions under which each of these may be 

 evoked have not yet been definitely ascertained. Whether the 

 splanchnic nerve, i.e. the sympathetic system, has a direct influence 

 on the movements of the stomach has been disputed. According to 

 Page May any effect produced by stimulation of this nerve, generally 

 consisting in diminished motor activity, is probably due to the 

 simultaneous influence on the vascular supply to the organ ; the 

 blood-vessels being constricted, an artificial anaemia is produced 

 which in itself is sufficient to account for diminished activity. Other 

 observers regard the splanchnic as having an influence on the stomach 

 similar to its action on the intestine, and regard it as the chief inhibitory 

 nerve to this organ. It is possible that the extent to which the 

 stomach is brought under the control of the sympathetic system 

 may vary in different species of animals. 



