e fore limb and hand were of some
distinct use is proved by the enormous size of the thumb-claw; while
the hand may not have conveyed food to the mouth, it may have served
to seize and tear the prey. As to the actual pose in feeding, there
can be little doubt as to its general similarity to that of the
_Raptores_ among the birds, as suggested to me by Dr. Wortman (see
fig. 10); one of the hind feet rested on the prey, the other upon the
ground, the body being further balanced or supported by the vertebrae
of the tail. The animal was thus in a position to apply its teeth and
exert all the power of its very powerful arched back in tearing off
its food. That the gristle of the bone or cartilage was very palatable
is attested not only by the toothmarks upon these bones, but by many
similar markings found in the Bone-Cabin Quarry.

_The Bird-Catching Dinosaur._ Of all the bird-like dinosaurs which
have been discovered, none possesses greater similitude to the birds
than the gem of the quarry, the little animal about seven feet in
length which we have named _Ornitholestes_, or the "bird-catching
dinosaur." It was a marvel of speed, agility, and delicacy of
construction. Externally its bones are simple and solid-looking, but
as a matter of fact they are mere shells, the walls being hardly
thicker than paper, the entire interior of the bone having been
removed by the action of the same marvelous law of adaptation which
sculptured the vertebrae of its huge contemporaries. There is no
evidence, however, that these hollow bones were filled with air from
the lungs, as in the case of the bones of birds. The foot is
bird-like; the hand is still more so; in fact, no dinosaur hand has
ever before been found which so closely mimics that of a bird in the
great elongation of the first or index-finger, in the abbreviation of
the thumb and middle finger, and in the reduction of the ring-finger.
These fingers, with sharp claws, were not strong enough for climbing,
and the only special fitness we have been able to imagine is that they
were used for the grasping of a light and agile prey (see figs. 17,
18.)

Another reason for the venture of designating this animal as the
"bird-catcher" is that the Jurassic birds (not thus far discovered in
America, but known from the _Archaeopteryx_ of Germany) were not so
active or such strong fliers as existing birds; in fact, they were not
unlike the little dinosaur itself. They were toothed, long-tailed