But the group is none the less interesting for the small number of forms included in it; for containing, as it does, the Dog, the animal of all others entitled to the name domestic, it yields in importance to neither of the larger groups, notwithstanding the varied series of creatures enclosed within their pale. Members of the Dog family are found in nearly all parts of the world, being absent only in the West Indian Islands, Madagascar, the eastern islands of the Malayan Archipelago, New Zealand, and the Polynesian Islands. When we say that the Dog is absent from those places, we mean, of course, _as a true native_. Wherever civilised man has penetrated, there his four-footed friend is sure to be found; but in the places just mentioned no Dog, Wolf, or Fox occurs as a true aboriginal. Very probably, the gigantic island of Australia should be added to the above list, as it is by no means certain that the Dingo, or wild Dog found there, has not been introduced by man. The Dogs form a sort of connecting link between the Cat-like species on the one hand, and the Bear-like group on the other. In the matter of being digitigrade, they agree with the Cats; the number of their teeth agrees with that of the Bears; in the character of the skull they come just half-way between the two. [Illustration: SIDE-VIEW OF WOLF’S SKULL. The letters have the same significance as in the figure of the Lion’s skull on p. 11.] On the under surface of the Dog’s skull there is found, in a corresponding position to the ear-drum swelling of the Cat (see p. 11), a similar rounded swelling, which, however, is smaller in proportion to the size of the skull, rougher in texture, and not so regular in shape, but sloping towards its outer aperture. Moreover, the margins of its outer aperture, round which the external ear is fixed, are produced outwards into a short tube or spout, thus making a small bony ear-passage beyond or external to the rim to which the drum membrane is attached. In the Cat, it will be remembered, there was no bony tube of this sort, but the drum parchment was flush with the margins of the opening of the drum cavity. Then the partition, which was so large in the Cat, dividing the cavity into two compartments, is here reduced to quite a low wall. Lastly, the bony clamp, which we mentioned in the Cat as being fixed quite closely against the hinder face of the bulla, is here separated from it by a small valley. These skull characters are very characteristic of the Cynoidea, and are therefore of great importance in the grouping of the Carnivora. The great arches of bone beneath the eye are, in the Dog, nothing like so large as in the Cat, owing to the smaller size of the jaw muscles which pass under them. The snout, however, is much longer, in correspondence with the increased number of the teeth.