his body crouching and flexuous, his tail lowered and wagging,
and ears depressed, he caresses his master. This contrast
in the attitudes and movements of these two carnivorous animals,
under the same pleased and affectionate frame of mind,
can be explained, as it appears to me, solely by their movements
standing in complete antithesis to those which are naturally assumed,
when these animals feel savage and are prepared either to fight
or to seize their prey.

In these cases of the dog and cat, there is every reason to believe
that the gestures both of hostility and affection are innate or inherited;
for they are almost identically the same in the different races
of the species, and in all the individuals of the same race,
both young and old.

I will here give one other instance of antithesis in expression.
I formerly possessed a large dog, who, like every other dog,
was much pleased to go out walking. He showed his pleasure
by trotting gravely before me with high steps, head much raised,
moderately erected ears, and tail carried aloft but not stiffly.
Not far from my house a path branches off to the right, leading to
the hot-house, which I used often to visit for a few moments, to look
at my experimental plants. This was always a great disappointment
to the dog, as he did not know whether I should continue my walk;
and the instantaneous and complete change of expression which came
over him as soon as my body swerved in the least towards the path
(and I sometimes tried this as an experiment) was laughable.
His look of dejection was known to every member of the family, and was
called his _hot-house face_. This consisted in the head drooping much,
the whole body sinking a little and remaining motionless; the ears