CHARACTERS OF PHALANGERS 



139 



common integument as in the Macropodidae. The hallux is oppos- 

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

 The pouch is well developed ; the stomach not sacculated ; u 

 caecum is present (except 

 in Tarsipes). 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 be 

 divided into four sub- 

 families. 



The first of these, that 

 of the Phalangeeinae, 

 contains the genera Phal- 

 anger (including Cuscus), 

 Acrohates, Distaechurus, 

 Bromicia, Gymnobelideus, 

 Petaurus, Petauroides, 

 I)actyloj)sila, Pseudochirus, 

 and Triclwsurus. 



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-sao often coalesced: 

 lungs with an azygos lobe. 



The second sub-family, Phascolaectinae (with the Koala only) 

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

 superior incisors three, but only one premolar above and below 



ect.cvcn 



IV 



Fig. 68. — Bones of leg and foot of Plialanger. asl. 

 Astragalus ; calc, caloanenm ; cub, cuboid ; 

 ect.cun, ecto-cuneiform ; ent.cwn, ento-cunei- 

 form ; fb, fibula ; mes.mn, meso-cuneiform ; 

 nax, navicular ; iib, tibia ; /- F, first to fifth 

 toes. (After Owen.) 



