CHAP. 78.—THE BELLY: ANIMALS WHICH HAVE NO BELLY.
WHICH ARE THE ONLY ANIMALS THAT VOMIT.
In those animals which have a stomach, below the diaphragm
the belly is situate. In other animals it is single, but in
those which ruminate it is double; in those, again, which
are destitute of blood, there is no belly, for the intestinal
canal commences in some of them at the mouth, and returns to
that part, as is the case with the sæpia and the polypus. In
man it is connected with the extremity of the stomach, and
the same with the dog. These are the only creatures that
have the belly more narrow at the lower part; hence it is,
too, that they are the only ones that vomit, for on the belly
being filled, the narrowness at its extremity precludes the food
from passing; a thing that cannot possibly be the case with
the animals in which the belly is more capacious at the extremity, and so leaves a free passage for the food to the lower
parts of the body.
