FOOD-STUFFS AND GLYCOGEN FORMATION 327 



organism there being, on account of the liberal ingestion of sugar, 

 sufficient carbohydrate to supply all the fuel necessary for the 

 tissues and hence being deposited as glycogen. A definite answer 

 to this question has been furnished by Ott by the use of the 

 method described above. This worker experimented on hens 

 which had been starved for five days, and in which the glycogen 

 in the entire body (according to Ktilz's analyses) could not have 

 been more than 2-130 grm. On the sixth day 50 grm. of chemically 

 pure glucose was given, and after about eight hours the hens were 

 killed. In a typical experiment the total glycogen in the body was 

 found to be 10- 3 5 grm. so that 8- 2 2 grm. glycogen had been 

 deposited. By an estimation of the nitrogen excretion it was calcu- 

 lated that 3'397 grm. glycogen might have been derived from proteid, 

 leaving 4-825 grm. undoubtedly derived from the dextrose ( 6 ). 



Of the remaining monosaccharides, Icevulose is an active 

 glycogen former and probably also galactose, 1 although there are 

 no observations on this sugar recorded by either of the above 

 methods. 



Of the di-saccharides, distinctly positive results have been 

 obtained by the above methods with cane-sugar and maltose, 

 but with lactose the results (on rabbits and hens at least) have 

 been entirely negative; no glycogen formation, undoubtedly 

 independent of proteid break-down, has been noticed by feeding 

 with this sugar. 



Of the polysaccharides, starch and dextrin are marked glycogen 

 formers. 



From an analysis of the foregoing results, we see that all 

 carbohydrates which on digestion yield dextrose or leevulose are 

 active glycogen formers. In the gastro-intestinal tract of all 

 animals there are ferments capable of converting cane - sugar, 

 maltose, and starches into one or other or both of these mono- 

 saccharides, and it is as such that the carbohydrate is absorbed 

 into the blood. Lactose, however, in hens and rabbits at least, 

 is not a glycogen former. On hydrolysis this di-saccharide yields 

 dextrose and galactose, and dextrose we have found to be the 

 most active of all glycogen formers. Why then does lactose not 



1 Fritz Voit has shown galactose to be completely oxidised in the organism 

 subcutaneous injections not appearing in the urine, as would have occurred 

 had it not been oxidised by the tissues and therefore to be undoubtedly a 

 glycogen former. 



