The more typical representatives of the group constitute the sub-family _Macropodinae_, in which the cutting-edges of the upper incisors are nearly level, or the first pair but slightly longer than the others (fig. 3). The canines are rudimentary and often wanting. The molars are usually not longer (from before backwards) than the anterior premolars, and less compressed than in the next section. The crowns of the molars have two prominent transverse ridges. The fore-limbs are small with subequal toes, armed with strong, moderately long, curved claws. Hind-limbs very long and strongly made. Head small, with more or less elongated muzzle. Ears generally rather long and ovate. The typical genus _Macropus_, in which the muzzle is generally naked, the ears large, the fur on the nape of the neck usually directed backwards, the claw of the fourth hind-toe very large, and the tail stout and tapering, includes a large number of species. Among these, the great grey kangaroo (_M. giganteus_, fig. 1) deserves special mention on account of having been discovered during Captain Cook's first voyage in 1770. The great red kangaroo (_M. rufus_) is about the same size, while other large species are _M. antilopinus_ and _M. robustus_. The larger wallabies, or brush-kangaroos, such as the red-necked wallaby (_M. ruficollis_) constitute a group of smaller-sized species; while the smaller wallabies, such as the filander (q.v.) (_M. muelleri_) and _M. thetidis_, constitute yet another section. The genus ranges from the eastern Austro-Malay islands to New Guinea. Nearly allied are the rock-wallabies of Australia and Tasmania, constituting the genus _Petrogale_, chiefly distinguished by the thinner tail being more densely haired and terminating in a tuff. Well-known species are _P. penicillata_, _P. xanthopus_ and _P. lateralis_. The few species of nail-tailed wallabies, _Onychogale_, which are confined to the Australian mainland, take their name from the presence of a horny spur at the end of the tail, and are further distinguished by the hairy muzzle. _O. unguifer_, _O. fraenatus_ and _O. lunatus_ represent the group. The hare-wallabies, such as _Lagorchestes leporoides_, _L. hirsutus_ and _L. consepicillatus_, constitute a genus with the same distribution as the last, and likewise with a hairy muzzle, but with a rather short, evenly furred tail, devoid of a spur. They are great leapers and swift runners, mostly frequenting open stony plains. [Illustration: FIG. 4.--Skull and teeth of Lesueuir's Rat-Kangaroo (_Bettongia lesueuiri_). c, upper canine. Other letters as in fig. 3. The anterior premolar has been shed.]