“If docile means stupid, well and good; in such a case the Camel is the very model of docility. But if the epithet is intended to designate an animal that takes an interest in its rider so far as a beast can, that in some way understands his intentions, or shares them in a subordinate fashion, that obeys from a sort of submissive or half-fellow-feeling with his master, like the horse or elephant, then I say that the camel is by no means docile—very much the contrary. He takes no heed of his rider, pays no attention whether he be on his back or not, walks straight on when once set agoing, merely because he is too stupid to turn aside, and then should some tempting thorn or green branch allure him out of the path, continues to walk on in the new direction simply because he is too dull to turn back into the right road. In a word, he is from first to last an undomesticated and savage animal, rendered serviceable by stupidity alone, without much skill on his master’s part, or any co-operation on his own save that of an extreme passiveness. Neither attachment nor even habit impress him; never tame, though not wide-awake enough to be exactly wild.” The two species breed together freely, and among the Yourouks of Asia Minor, hybrids, or mules, the produce generally of a male Bactrian and a female Arabian camel are preferred to either of the pure breeds. Fossil remains of Camels are found in the Pliocene of the Siwalik Hills in Northern India. These differ from the existing representatives of the genus in having a vertical ridge at the antero-external angle of the lower molars, whereby they resemble _Auchenia_; their cervical vertebræ are also intermediate in structure between those of the latter and the existing Camels. A fossil Camel is also found in the Pleistocene of Algeria.