s
quite unsatisfactory. Perrault and others supposed that it contributed
to the security of those animals, which are at once voracious and timid,
by showing the necessity of their remaining long employed in chewing in
an open pasture; but the Indian buffalo ruminates, although it does not
fly even from the lion; and the wild goat dwells in Alpine countries,
which are inaccessible to beasts of prey.

Whatever may be our ignorance of the cause or the object of rumination,
it is certain that the nature of the food has a considerable influence
in increasing or diminishing the necessity for the performance of that
function. Thus, dry food requires to be entirely subjected to a second
mastication, before it can pass into the many-plies and reed; whilst a
great portion of that which is moist and succulent passes readily into
those cavities, on its first descent into the stomach.

It has already been shown by the illustration, (p. 4,) that the paunch
is the largest of the four cavities; but this is not the case with the
stomach of the young calf, which, while it continues to suck, does not
ruminate; in this case the _reed_, which is the true digestive cavity,
is actually larger than the other three taken together.

When the calf begins to feed upon solid food, then it begins to
ruminate; and as the quantity of solid food is increased, so does the
size of the paunch increase, until it attains its full dimensions. In
this latter case, the _paunch_ has become considerably larger than the
other three cavities taken together.

A curious modification of an organ to adjust itself to the altered
condition of the animal is beautifully shown in the instance now under
consideration, the nature of which will be easily understood by a
reference to the following diagrams, giving the exact relative
proportions of the different cavities of the stomach to each other in
the young calf and in the full-grown cow.

[I am informed by Professor Symonds, of the Royal Veterinary
College, that the two following sketches should be placed in
the page so as to be viewed with the oesophagus to the right,
and the pylorus to the left, instead of being, as they now are,
at the top and the bottom; but as the present object is only to
show the relative sizes of the different cavities, the error is
not of much consequence.]

The letters refer to the same parts in each figure: _a_, the paunch;
_b_, the honeycomb bag; _c_,