ful to its enemies or rivals, and is generally accompanied by various voluntary movements adapted for the same purpose, and by the utterance of savage sounds. Mr. Bartlett, who has had such wide experience with animals of all kinds, does not doubt that this is the case; but it is a different question whether the power of erection was primarily acquired for this special purpose.
"With the carnivora the erection of the hair seems to be almost universal, often accompanied by threatening movements, the uncovering of the teeth, and the utterance of savage growls. The enraged lion erects his mane. The bristling of the hair along the neck and back of the dog, and over the whole body of the cat, especially on the tail, is familiar to every one. With the cat it apparently occurs only under fear; with the dog, under anger and fear; but not, as far as I have observed, under abject fear, as when a dog is going to be flogged by a severe game-keeper. If, however, the dog shows fight, as sometimes happens, up goes his hair. I have often noticed that the hair of a dog is particularly liable to rise, if he is half angry and half afraid, as on beholding some object only indistinctly seen in the dusk.
Fig. 8.
Swan driving away an Intruder.—(Drawn from Life by Mr. Wood.)
"I have been assured by a veterinary surgeon that he has often seen the hair erected on horses and cattle, on which he had operated and was going again to operate.
"Birds belonging to all the chief orders ruffle their feathers when angry or frightened. Every one must have seen two cocks, even quite