laughter. Some persons speak of the grin as a smile, but if it had
been really a smile, we should see a similar, though more pronounced,
movement of the lips and ears, when dogs utter their bark of joy; but
this is not the case, although a bark of joy often follows a grin. On
the other hand, dogs, when playing with their comrades or masters,
almost always pretend to bite each other; and they then retract, though
not energetically, their lips and ears. Hence I suspect that there is a
tendency in some dogs, whenever they feel lively pleasure combined with
affection, to act through habit and association on the same muscles, as
in playfully biting each other, or their masters hands.
I have described, in the second chapter, the gait and appearance of a
dog when cheerful, and the marked antithesis presented by the same
animal when dejected and disappointed, with his head, ears, body, tail,
and chops drooping, and eyes dull. Under the expectation of any great
pleasure, dogs bound and jump about in an extravagant manner, and bark
for joy. The tendency to bark under this state of mind is inherited, or
runs in the breed: greyhounds rarely bark, whilst the Spitz-dog barks
so incessantly on starting for a walk with his master that he becomes a
nuisance.
An agony of pain is expressed by dogs in nearly the same way as by many
other animals, namely, by howling writhing, and contortions of the
whole body.
Attention is shown by the head being raised, with the ears erected, and
eyes intently directed towards the object or quarter under observation.
If it be a sound and the source is not known, the head is often turned
obliquely from side to side in a most significant manner, apparently in
order to judge with more exactness from what point the sound proceeds.
But I have seen a dog greatly surprised at a new noise, turning, his
head to one side through habit, though he clearly perceived the source
of the noise. Dogs, as formerly remarked, when their attention is in
any way aroused, whilst watching some object, or attending to some
sound, often lift up one paw (fig. 4) and keep it doubled up, as if to
make a slow and stealthy approach.
A dog under extreme terror will throw himself down, howl, and void his
excretions; but the hair, I believe, does not become erect unless some
anger is felt. I have seen a dog much terrified at a band of musicians
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