FUNCTIONS OP THE STOMACH. 



299 



tributed throughout the walls of the stomach and a free end 

 brought out to the exterior and the circuit closed under the 

 same conditions, an equally strong current being used, the 

 results would undoubtedly have been similar. The vagus may 

 have acted as a mere conductor for the transmission of a cur- 

 rent which would have simultaneously stimulated all the secre- 

 tory mechanism: glands, vessels, sympathetic fibers, and mus- 

 cles. 



We know that application of the current to the skin causes 

 contraction of the underlying muscles; can we doubt that the 

 gastric tissue may be similarly affected when so perfectly 'dis- 

 tributed a conductor as the fibers of the vagus is employed 

 for its transmission? It is evident that a current may serve 

 a useful purpose as it did in Claude Bernard's experiments on 

 the submaxillary or in Laffont's on the mammary gland, after 

 vasodilation as a result of division of the nerve had previously 

 shown its physiological purpose; by merely restoring the nor- 

 mal state, it afforded confirmatory evidence and a basis for 

 logical deductions. In Pawlow's experiments it is given the 

 leading role, however, and, pending further elucidation, it may 

 prove wise to accept as basis of our analysis of the whole sub- 

 ject the following remark of Professor Howell's: "Our knowl- 

 edge of the means by which the flow of gastric secretion is 

 caused during normal digestion, and of the varying conditions 

 which influence the flow, is as yet quite incomplete," and to 

 build up the process with the aid of what newer factors our 

 own views may suggest. 



We may assume, with the quantity of evidence already 

 adduced as groundwork, that the sympathetic fibers are inti- 

 mately connected with the functional mechanism of the organ. 

 As no true motor nerves have been traced to the stomach, and 

 as we have attributed to the sympathetic system motor func- 

 tions, may Auerbach's and Meissner^s plexuses both sympa- 

 thetic structures not supply all the efferent fibers required by 

 the glands and the muscular coats? Beginning with Auer- 

 bach's plexus, we know that after piercing the external serous 

 coat of the stomach its nerves pass between the circular and 

 longitudinal muscular layers, where they form a close net- 

 work strewn with ganglia, the whole constituting the plexus. 



