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New York AGRICULTURAL EXPERIMENT STATION. 163 
capillaries of the intestine and carried as sugar to the liver in the 
portal blood. The sugar carried to the liver, becoming through 
some action of the hepatic cell-substance dehydrated into glycogen 
or animal starch, as it has been called, the process being a reverse 
of that by which in the alimentary canal starch is hydrated into 
sugar through the action of the salivary and pancreatic ferments. 
The glycogen that is stored up in the liver may from time to 
time be converted into fat and used in the animal economy, but 
there is no certain evidence upon this fact. Part of the glycogen 
at least, previously stored up in the liver is from time to time 
_ reconverted into sugar and is slowly discharged into the hepatic 
blood for use in the body. 
Waste Products. 
The elimination of waste products of the body takes place 
mainly through the lungs, the skin and the kidneys, the former 
_ excreting carbonic acid, the latter urea, salts and water, while the 
skin eliminates water and some salts. The undigested portion of 
the food together with small portions of the several secretions 
poured into the alimentary canal, escape in the faeces. 
In his Manual on Cattle Feeding, Dr. Armsby, who has made 
a careful study of the results obtained, mainly in Europe, up to 
1880, says, in speaking of the Hormation of Fat in the Body that 
“for the fact of the formation of fat in the body from other sub- 
q _ stances no special proofs need be adduced: it is sufficiently evi- 
_ dent from daily experience, especially in fattening and in milk 
2 production.” 
| To such sweeping assertion, most decided objection must be 
i made, and an entire dissent from the statement that “ daily expe- 
2 eo especially in fattening and milk production” proves or 
_ even renders it probable that the fat stored up in the body or 
a BP eroted:; in the milk is produced from any other constituent of 
_ the food than the fat. 
_ A careful survey of the matter.as it is presented by Dr. Armsby, 
‘i fails to show me a single argument which clearly establishes such 
_ a fact, unless we except only the case of the fly’s eggs hatched in 
_and fed upon blood. The experiments cited where dogs were fed 
solely upon fat, free from meat and failed to excrete all the car- 
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