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 This group contains but one family, the Orycteropodidae, of which there is but a single genus.

The Aard Vark (earth-pig), genus Orycteropus, is characterised by its heavy build, the body being covered by rather coarse and not very abundant hair; the snout is long and pig-like, with round nostrils at its end; the ears are long, erect, and pointed; the tail is very thick at first, so that it has been aptly described as "a tapering of the body to a point." The fore-limbs are four-toed, the hind five-toed.



In the skull there is a complete though slender zygoma; the premaxillaries, though small, are not so rudimentary as in the American Edentates. The annular tympanic is not ankylosed to the surrounding bones, a character found in other low mammals. Contrary to what is found in Manis, Orycteropus has a huge lachrymal. There are thirteen dorsal and seven lumbar vertebrae. The clavicle is well developed. Orycteropus is peculiar among Edentates in that the ischia do not unite with the vertebral column. The femur has a third trochanter.

As mentioned on p. 162, the Aard Vark is diphyodont like normal mammals. The permanent teeth consist of five molars and premolars on each side of each jaw; the first two of these are premolars, and are simpler in their form than the succeeding two teeth, which are partly divided by a median furrow into two halves. These teeth are also peculiar in that they consist entirely of vaso-dentine. They have been compared in minute structure to those of the Ray Myliobates. According to Mr. Oldfield