348 THE ADRENAL, GENERAL MOTOR, AND VAGAL SYSTEMS. 



penetrate through these, so could an equally viscid substance, 

 and with still greater ease, the blood-plasma. As "no injection 

 in the intercellular bile-canaliculi nor in the perivascular lym- 

 phatics nor between the cells" could be detected, the penetra- 

 tion of the gelatin can hardly be ascribed to undue stress. 

 "There being," also, "no diffusion of carmine nor any staining 

 of the cells or nuclei by carmine," the nucleo-mural net-work to 

 which we refer must be an independent structure, circumscrib- 

 ing two kinds of cavities: the canals and the vacuoles. The ca- 

 nals communicating with the exterior of the cell, they are prob- 

 ably the receiving cavities, while the vacuoles, their neighbors, 

 are the spaces in which the useful products of metabolism are 

 accumulated. The canals themselves, continuing until Kupf- 

 fer's vesicle is reached, would thus pour their excretory con- 

 tents bile and its various constituents into this cavity, and 

 this, in turn, would convey them to the intercellular bile-capil- 

 laries through its own canals. 



Whether so direct a connection between the intercellular 

 capillaries and the bile-channels through the cell exists is a 

 point to be determined. Bile and the various bodies excreted 

 with it would be voided as are the intestinal contents, the 

 canalicular walls taking up certain elements, while physiolog- 

 ical substances would be mixed with the substances in transit 

 for definite purposes. 



The first question that suggests itself is the following: 

 Is glycogen formed during the active functional activity of the 

 liver (during digestion) or during its passive state (between 

 meals)? We have seen that the production of urea is increased 

 immediately after a meal; we have evidence, therefore, that an 

 active state based upon increased oxidation processes must 

 prevail, and that it is during digestion that the substances out 

 of which glycogen is formed reach the liver, i.e., while the 

 oxidizing substance is present in the capillaries. This suggests 

 that the oxidizing substance must itself take part in the forma- 

 tion of glycogen, though perhaps indirectly, and also in the 

 elaboration of bile. 



The main coloring constituent of bile, bilirubin, we have 

 previously considered as the product of a reaction in the inter- 

 cellular capillaries. As such it is probably eliminated with the 



