CHARACTERS OF PHALANGERS 



139 



common integument as in the Macropodidae. The haUux is o])])os- 

 ahle and nailless. The tail is nearly always long and prehensile. 



ect.cu^n 



The pouch is well developed ; the stomach not sacculated ; 

 caecum is present (except 

 in 2\(Tsipes). These are 

 really the principal dis- 

 tinctions between the two 

 families. In addition, it 

 may be mentioned that the 

 lower incisors have not a 

 scissor-like action as in the 

 Kangaroos. 



The Phalangers may Its 

 divided into four sub- 

 families. 



The first of these, that 

 of the Phalangekinae, 

 contains the genera Phal- 

 anger (including Cusctis), 

 Acrohates, Distaechurn s, 

 Drotnicia, Gymnohelideus, 

 Pe t a 'II r u s, Fe t a uroides, 

 UactT/lupsila, Fseudochirus, 

 and TrichosuTUs. 



These genera agree in 

 the following generalities: — 

 Tail well developed, often 

 very long ; three incisors 

 above, and at least two pre- 

 molars both above and 

 below ; caecum long and 

 simple ; stomach without 

 a cardiac gland ; liver not 

 very complicated by second- 

 ary furrows, with a distinct 

 caudate lobe; the vaginal median culs-de-sac often coalesced; 

 lungs with an azygos lobe. 



The second sul)-family, Phascolarctinae (with the Koala only), 

 is thus characterised : — Tail rudimentary ; cheek-pouches present : 

 superior incisors three, 1 >ut only one premolar above and below ; 



Fig. 68. — Bones of leg and foot of Plialanger. as(. 

 Astragalus ; calc, calcaneuni ; cub, cuboid : 

 ecf.cKii, ecto-cuiieiform ; ent.cna, eiito-cuiiei- 

 forni ; fb, fibula; mefi.cini, nieso-cuneiforin ; 

 7iar, navicular ; tib, tibia ; /- T, first to fifth 

 toes. (After Owen.) 



