FORMATION OF SUGAR IN THE LITER. 339 



The researches of Bernard and others, however, have 

 shown that the sugar is not formed at once at the liver, 

 but that this organ has the power of producing a peculiar 

 ternary substance, which is readily convertible into sugar 

 when in contact with any animal ferment. This substance 

 has received from various chemists the different names of 

 glycose, glycogen, glycogenic substance, glycocene, animal 

 starch, amylon, amyloid substance, hepatin. 



There are two chief theories concerning the immediate 

 destination of this substance, (i.) According to Bernard 

 and most other physiologists, its conversion into sugar 

 takes place rapidly during life, and the sugar is conveyed 

 away by the blood of the hepatic veins to be consumed in 

 respiration at the lungs. (2.) Pavy and others believe that 

 the conversion into sugar only occurs after death, and that 

 during life no sugar exists in healthy livers, the amyloid 

 substance or hepatin being prevented by some force from 

 undergoing the transformation. The chief arguments 

 advanced by Pavy in support of this view are, first, that 

 scarcely a trace of sugar is found in blood drawn during 

 life from the right ventricle, or in blood collected from the 

 right side of the heart immediately after an animal has 

 been suddenly deprived of life, while if the examination be 

 delayed for a little while after death, sugar in abundance 

 may be found in such blood ; secondly, that the liver, 

 like the venous blood in the heart, is, at the moment of 

 death, almost completely free from sugar, although after- 

 wards its tissue speedily becomes saccharine, unless the 

 formation of sugar be prevented by freezing, boiling, or 

 other means calculated to interfere with the action of a 

 ferment on the amyloid] substance of the organ. Instead 

 of adopting Bernard's view, that normally, during life, it 

 passes as sugar into the hepatic venous blood, and thereby 

 is conveyed to the lungs to be further disposed of, Pavy 

 inclines to believe that it is destined to enter the in- 

 testinal canal through the biliary ducts, and then possibly 



