GLYCOGBN AND ITS FORMATION. 351 



used by the organism. Indeed, they (or at least a part of their 

 decomposition products) are again absorbed by the intestinal 

 mucous membrane, and, passing through the venous channels, 

 probably take up therein and transfer to the hepatic cells what 

 waste-matter they are to carry to the intestinal tract. We 

 thus have in the cellular canaliculi two acids endowed with 

 powerful affinities and an active reagent, the oxidizing sub- 

 stance, to account for the processes of a chemical nature con- 

 nected with the functions of the hepatic cell. 



Of course, all this involves the necessity of showing, as a 

 controlling factor, that products of combustion are also pres- 

 ent. The following lines by Professor Howell give this feature 

 due emphasis; referring to bile, he says: "The secretion con- 

 tains also a considerable, though variable, quantity of C0 2 gas, 

 held in such loose combination that it can be extracted with a 

 gas-pump without the addition of acid. The presence of this 

 constituent serves as an indication of the extensive metabolic 

 changes occurring in the liver-cells." 



Again, the element of nervous control implied when we 

 referred to the oxidizing substance contributed by the hepatic 

 artery must be shown. We have seen that the vagus was the 

 active nerve during functional activity of the stomach; that it 

 should likewise govern hepatic functions is obvious. That such 

 is the case is sustained by no less an authority than Claude 

 Bernard, to whom we owe the discovery of glycogen one of 

 his greatest achievements and whose conceptions have been 

 almost all sustained by all the labor bestowed upon them since. 

 He not only found that the vagus was the predominating nerve 

 in the liver, but that its section also suppressed its glycogenic 

 function. 



The fate of glycogen, its conversion into sugar for the use 

 of muscular and other tissues, may now be analyzed with 

 greater facility. 



Our analysis of muscular functions led us to the deduction 

 that the contractile elements contained a substance, myosino- 

 gen, which, when brought into contact with the oxidizing sub- 

 stance of the plasma, became the source of the muscle's work- 

 ing energy. Ample evidence was afforded to show that we 

 were dealing with an oxidation process, the intensity of which 



