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 skeletons of both being in situ; this animal was about the size of a Shepherd Dog. The actual Dog of to-day is divisible into more than 180 different breeds; but in a work upon "Natural History" it would seem out of place to enumerate and characterise these artificial products. Authors vary in their opinion as to what stock gave rise to the domestic races of the past and of to-day. The Jackal, the Bunasu (C. primaevus), the Indian Wolf (C. pallipes), have been proposed as likely ancestors. It is more probable that there is much admixture, and that various wild types have been selected by man in various countries.

Extinct Canidae.—Many of the existing species of Canidae are also to be found in Pleistocene deposits of the countries which they now inhabit. A few show a wider range in the immediate past than in the present. Thus Lycaon (L. anglicus) has been met with in caves in Glamorganshire, while Icticyon of South America appears to be congeneric with Speothos of the Brazilian caves. The African Otocyon seems to occur in deposits in India. There are also numerous extinct species belonging to the genus Canis, which extend as far back as the Pliocene.

The earlier types of Dogs have been placed in different genera. Cynodictis is an Eocene form from European strata. The skull is decidedly Civet-like, with a short snout. The fore- and hind-feet were five-toed, with well-developed pollex and hallux. The dentition was that of modern Dogs, the molars being two in the upper and three in the lower jaw. The general aspect of the creature and the form of the skeleton was much like that of the Viverrine genus Paradoxurus, of which, as well as of the Dogs, Cynodictis might have been an ancestor.

Simocyon of the Upper Miocene serves as the type of a separate sub-family of Dogs, Simocyoninae. The skull is short, broad, and high; the shortening of the skull affecting the jaws has reduced the teeth greatly; the first three premolars are very small, fall out soon, and are thus often deficient. There are only two molars in each jaw. This type is of course nowhere near the ancestral Dog. It is a much-specialised branch of an early type. Cephalogale is less specialised; there are the usual four premolars. Enhydrocyon is an intermediate form; it has lost one premolar in each jaw.

Amphicyon, forming the type of another sub-family, Amphicyoninae, though usually placed among the Dogs, presents us with