EXPERIMENTS ON DIGESTION. 
711 
less, a reservoir like the stomach, in which the last act of digestion 
is accomplished. Its resemblance to the stomach is particularly 
evident in the animals which feed on the larger vegetable sub- 
stances — the ruminants, horses, the rodentia, the pachydermata, in 
whom we should challenge this viscus as a stomach, not only on 
account of its size and capacity, but its very form ; but it is small 
in the carnivorous animals, and it is in a manner lost in those 
who live on fruits, and saccharine and feculent roots, as the bear, 
the badger, and the marten. We are justified by this in consider- 
ing it as a kind of stomach, as Yiridet had previously done. It is 
even a secreting organ. There are in this intestine, and its large 
and numerous glands, an acid and solvent fluid, which mingles 
with those portions of the food that are difficult to digest, and 
which seems to tarry a considerable time in the caecum for that 
purpose. It contains also a little albumen, which we have found 
in the dog, but in greater abundance in animals that live on vege- 
table substances. The addition of the albumen contributes, per- 
haps, to complete the assimilation of the food dissolved by the fluid 
which this stomach contains. 
Nature seems to make a last effort in the caecum to extract 
every thing which the aliment can yet contain of a soluble nature ; 
and it is in this viscus that the true intestinal excrement is pro- 
duced under the form of a soft bouillie , of a brown or yellow-brown 
colour, and with its peculiar faecal odour proceeding from a volatile 
oil, which, apparently, is chiefly secreted by the caecum. During 
the greater part of the time, also, there is going forward in this 
viscus a decomposition of the matters which it contains, excited by 
the natural heat of the part, and accompanied by the disengage- 
ment of hydro-sulphuric acid gas. 
The Nature of the Contents of the Remainder of the large Intes- 
tine and of the Rectum. — The remains of the food, after having 
remained during a certain time in the caecum, and being there 
mingled with the acid fluid which that viscus secretes, are forced 
on by little and little into the rectum, by the vermicular action of 
the muscular tunic of that intestine and of the colon. They insen- 
sibly accumulate, because the sphincters of the anus oppose their 
expulsion. In proportion as they advance along the large intestine, 
and approach the rectum, their consistence increases, and also their 
dryness — their brown colour and the excrementitious smell. The 
portions of the remnants of the food which have been dissolved by 
the acid fluid of the caecum are completely absorbed. During 
their passage they mingle a little with the mucus secreted by the 
glands of the large intestine. Finally, the undissolved residue of 
the aliment remains, with the intestinal mucus now become of 
