The same phenomenon is seen in many kinds of Dog in the Old World. The Shepherd Dog of the plains of Hungary is white or reddish-brown, has a sharp nose, short erect ears, shaggy coat, and bushy tail, and so much resembles a Wolf, that Mr. Paget, who gives the description, says he has known a Hungarian mistake a Wolf for one of his own Dogs. There is also a close resemblance between some of the Indian Pariah Dogs and the Indian Wolf. Some of the domestic Dogs of Egypt, both at the present day and in the condition of mummies, closely resemble the Wolf of that country; “whereas the domestic Dogs of Nubia, and certain other mummied Dogs, have the closest relation to a wild species of the same country ... which is only a form of the common Jackal.” Dogs have, moreover, been known to cross with Jackals as well as with Wolves. Lastly, in Africa, some of the natives assert that their half-tamed Dogs are derived from Foxes; and the Dogs of the Bosjesman have a striking resemblance to the black-backed Jackal (_C. mesomelas_), which, as we shall see, is a South African variety. These facts are so significant and so important that they in reality leave only one difficulty to be settled, and that is the question of voice. As we stated above, all domestic Dogs bark, while all wild _Canidæ_ express their feelings only by howls. But the difficulty here is not so great as it seems. Some domestic Dogs left on the island of Juan Fernandez entirely lost the habit of barking in thirty-three years, and a few individuals removed after that period only re-acquired it very slowly; thus, domestic Dogs allowed to run wild forget how to bark. On the other hand, Jackals, wild Dogs, and Wolf-pups reared by bitches, readily acquire the habit. Thus the last stumbling-block in the argument disappears, and we are forced to agree with Mr. Darwin, from whom many of the above facts are taken,[96] that “it is highly probable that the domestic Dogs of the world have descended from two good species of Wolf (_C. lupus_ and _C. latrans_), and from two or three other doubtful species of Wolves (namely, the European, Indian, and North African forms); from at least one or two South American Canine species; from several races or species of the Jackal; and perhaps from one or more extinct species;” and that the blood of these, “in some cases mingled together, flows in the veins of our domestic breeds.” There is no animal so interesting as the Dog for the study of the relation between man and the lower animals in the matter of instinct, reason, conscience, and the like. As no animal has been so thoroughly domesticated, and so systematically trained and educated, so none has developed in the same degree those higher endowments which are often considered as the exclusive attributes of humanity, such as reasoning power, a sense of right and wrong, of property, and of number.