fragment of its various parts
and organs.

"Every organized individual forms an entire system of its own, all the
parts of which naturally correspond, and concur to produce a certain
definite purpose, by reciprocal reaction, or by combining towards the
same end. Hence none of these separate parts can change their forms
without a corresponding change in the other parts of the same animal,
and consequently each of these parts, taken separately, indicates all
the other parts to which it has belonged. Thus, as I have elsewhere
shown, if the viscera of an animal are so organized as only to be fitted
for the digestion of recent flesh, it is also requisite that the jaws
should be so constructed as to fit them for devouring prey; the claws
must be constructed for seizing and tearing it to pieces; the teeth
for cutting and dividing its flesh; the entire system of the limbs,
or organs of motion, for pursuing and overtaking it; and the organs of
sense for discovering it at a distance. Nature must also have endowed
the brain of the animal with instincts sufficient for concealing itself
and for laying plans to catch its necessary victims....

"To enable the animal to carry off its prey when seized, a corresponding
force is requisite in the muscles which elevate the head, and this
necessarily gives rise to a determinate form of the vertebrae to which
these muscles are attached and of the occiput into which they are
inserted. In order that the teeth of a carnivorous animal may be able to
cut the flesh, they require to be sharp, more or less so in proportion
to the greater or less quantity of flesh that they have to cut. It is
requisite that their roots should be solid and strong, in proportion to
the quantity and size of the bones which they have to break to pieces.
The whole of these circumstances must necessarily influence the
development and form of all the parts which contribute to move the
jaws...."

After these observations, it will be easily seen that similar
conclusions may be drawn with respect to the limbs of carnivorous
animals, which require particular conformations to fit them for rapidity
of motion in general; and that similar considerations must influence the
forms and connections of the vertebrae and other bones constituting the
trunk of the body, to fit them for flexibility and readiness of motion
in all directions. The bones also of the nose, of the orbit, and of
the ears require certain forms and structures to f