As regards the teeth, in all cases except the wombats the number of upper incisors differs from that of the corresponding lower teeth.
- The third and last sub-order of marsupials is the Diprotodontia, which is exclusively Australasian and includes the wombats, koala, cuscuses, kangaroos and their relatives.
The first family, Phascolomyidae, is typified by the wombats; but according to the view adopted by Mr H.
In the wombats (Phascolomys) the dentition is i.
Presents resemblances both to the wombats and the phalangers, but is nearer to the former than to the latter.
Australia is inhabited by at least if o different species of marsupials, which is about two-thirds of the known species; these have been arranged in five tribes, according to the food they eat, viz., the grass-eaters (kangaroos), the root-eaters (wombats), the insect-eaters (bandicoots), the flesh-eaters (native cats and rats), and the fruit-eaters (phalangers).
In general form and action wombats resemble small bears, having a somewhat similar shuffling manner of walking, but they are still shorter in the legs, and have a broader and flatter back.
Fossil remains of wombats, some of larger size than any now existing, have been found in caves and Pleistocene deposits in Australia.
There seems to be no doubt that fossilized remains of the dingo occur intermingled with those of the extinct Australian mammals, such as giant kangaroos, giant wombats and the still more gigantic Diprotodon.
Moreover, with the exception of the wombats, the number of pairs of incisors in the upper always exceeds those in the lower.