e--has also sharp teeth, adapted for tearing up the flesh of its
victim, and a particular type of stomach, quite different from that of
herbivorous creatures. This adaptation of all the parts of the animal
to one another extends to the most diverse parts of the organism, and
enables the skilled anatomist, from the observation of a single typical
part, to draw inferences as to the structure of the entire animal--a
fact which was of vast aid to Cuvier in his studies of paleontology. It
did not enable Cuvier, nor does it enable any one else, to reconstruct
fully the extinct animal from observation of a single bone, as has
sometimes been asserted, but what it really does establish, in the hands
of an expert, is sufficiently astonishing.

"While the study of the fossil remains of the greater quadrupeds is more
satisfactory," he writes, "by the clear results which it affords, than
that of the remains of other animals found in a fossil state, it is also
complicated with greater and more numerous difficulties. Fossil shells
are usually found quite entire, and retaining all the characters
requisite for comparing them with the specimens contained in collections
of natural history, or represented in the works of naturalists. Even the
skeletons of fishes are found more or less entire, so that the general
forms of their bodies can, for the most part, be ascertained,
and usually, at least, their generic and specific characters are
determinable, as these are mostly drawn from their solid parts. In
quadrupeds, on the contrary, even when their entire skeletons are
found, there is great difficulty in discovering their distinguishing
characters, as these are chiefly founded upon their hairs and colors and
other marks which have disappeared previous to their incrustation. It is
also very rare to find any fossil skeletons of quadrupeds in any degree
approaching to a complete state, as the strata for the most part only
contain separate bones, scattered confusedly and almost always broken
and reduced to fragments, which are the only means left to naturalists
for ascertaining the species or genera to which they have belonged.

"Fortunately comparative anatomy, when thoroughly understood, enables
us to surmount all these difficulties, as a careful application of its
principles instructs us in the correspondences and dissimilarities of
the forms of organized bodies of different kinds, by which each may be
rigorously ascertained from almost every