DIPROTODONTIA. 



535 



FiQ. 279. — Skull and teeth of Bettongia lesiieuri. c canine : t in- 

 cisors ; pm premolar ; m molars (from Flower and Lj-dekker). 



it bvit not replaced ; the milk premolar is shed usually before the fourth 

 molar appears, and all the grinding teeth move forward in the skull with 

 increasing age as in elephants and some sirenians ; the lower incisors 

 are long, and can be used against one another in a scissor-like maruier. 

 3Iore than 60 species distributed all over the Australian region. 



Sub-fam. 1. Macropodinae. With long hairy tail, without hal- 

 lux ; with minute or absent canine. Macropus Shaw (Halniaturus), 

 kangaroos and wallabies, about 23 species, varying in size from that 

 of a rabbit to 

 tliat of man, 

 AustraKa, N. 

 Guinea, E. 

 half of Aus- 

 tro - Malaya ; 

 M. giganteus 

 Zimm., Aus- 

 tralia, except 

 the extreme 

 north, and 

 Tasmania. 

 P etrogale 

 Gray, rock- 

 wallabies, 

 Australia, but 

 notTasmania, 



6 species. Onychogale Gray, nail-tailed wallabies, with homy ex- 

 crescence at tip of tail, Australia, not Tasmania. Lagorchestes 

 Gould, hare-wallabies, Australia, not Tasmania, 3 species. 

 Dorcopais Schleg. and Miill., 3 species, N. Guinea. Dendrolagus 

 Schleg. and Miill-, tree kangaroos, arboreal, hardly macropodiform, 

 N. Guinea anxl North Queensland, 5 species. Lagostrophus Thomas, 



1 species, W. Australia. Extinct 

 genera, Palorchestes Ow., Sthen- 

 urus Ow., Synaptodus de Vis ; 

 Pleistocene, Australia. 



Sub-fam. 2. Potoroinae. Rat- 

 kangaroos, with long hairy tail, 

 without hallux ; with canines, 

 generally well developed ; pre- 

 molars ^ith large compressed 

 crowns, and usually grooved 

 on the inner and outer sur- 

 faces* (Fig. 279) ; small animals. 

 Aepyprymmis Garrod, E. Aus- 

 tralia, 1 species. Bettongia Gray, 

 Australia and Tasmania, 4 

 species. Caloprymnus Thomas, 

 S. Australia, 1 species. Poto- 

 rcnis Desm. (Hypsiprymmta HI.), Aust. and Tasmania, 3 species. 



Sub-tam. 3. Hypslprymnodontidae. With naked scaly tail and 

 an opposable hallux ; intermediate to Phalangeridae ; one species 



Fig. 280.—Phalanger celebenHs. Pes shoW' 

 ing syndactylism (from O. Thomas). 



As in some of the extinct Allotheria, see p. 541. 



