Fig. 71.—Wombat. Phascolomys wombat. × 1⁄12.
Sub-Fam. 3. Phascolomyinae.—Phascolomys, the Wombat, is the only genus of this sub-family. This animal has the appearance of a heavily-built Marmot, like which it has a mere stump for a tail, and a pair of strong chisel-shaped and Rodent-like incisors, which, however, differ from those of Rodents in having a complete coating of cement. All the teeth of the animal are rootless, and there are no canines. The incisors have enamel on the front and lateral faces only. The dental formula is I 1/1 C 0/0 Pm 1/1 M 4/4. The affinities with other Diprotodont Marsupials are shown by the commencing syndactyly of the second and third toes. The rhinarium is naked or hairy. There is a rudimentary cheek-pouch, as in Phascolarctos. The Wombat has, like the Koala, and also the Beaver—which does away with some of the value of the comparison—a peculiar gland-patch in the stomach, a raised area of collected glands. In no other Marsupial is such a structure found, "whilst in the two forms under consideration its identity is almost precise. That such a unique structure should have been independently developed in two forms unrelated to each other, appears to me to be in the highest degree improbable." This is Mr. Forbes' opinion. It might be strengthened by adding the observation that, as there are other points of likeness between the Wombat and the Koala, it seems more unlikely that a structure so nearly identical should have been twice
