With respect to the upright position of the tail, it seems to depend
(but whether this is really the case I know not) on the elevator
muscles being more powerful than the depressors, so that when all the
muscles of the hinder part of the body are in a state of tension, the
tail is raised. A dog in cheerful spirits, and trotting before his
master with high, elastic steps, generally carries his tail aloft,
though it is not held nearly so stiffly as when he is angered. A horse
when first turned out into an open field, may be seen to trot with long
elastic strides, the head and tail being held high aloft. Even cows
when they frisk about from pleasure, throw up their tails in a
ridiculous fashion. So it is with various animals in the Zoological
Gardens. The position of the tail, however, in certain cases, is
determined by special circumstances; thus as soon as a horse breaks
into a gallop, at full speed, he always lowers his tail, so that as
little resistance as possible may be offered to the air.
When a dog is on the point of springing on his antagonist, he utters a
savage growl; the ears are pressed closely backwards, and the upper lip
(fig. 14) is retracted out of the way of his teeth, especially of his
canines. These movements may be observed with dogs and puppies in their
play. But if a dog gets really savage in his play, his expression
immediately changes. This, however, is simply due to the lips and ears
being drawn back with much greater energy. If a dog only snarls at
another, the lip is generally retracted on one side alone, namely
towards his enemy.
Head of Snarling Dog. Fig 14
{illust. caption = FIG. 14. Head of snarling Dog. From life, by Mr.
Wood.
The movements of a dog whilst exhibiting affection towards his master
were described (figs. 6 and 8) in our second chapter. These consist in
the head and whole body being lowered and thrown into flexuous
movements, with the tail extended and wagged from side to side. The
ears fall down and are drawn somewhat backwards, which causes the
eyelids to be elongated, and alters the whole appearance of the face.
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