xx. 6 



PIIALANGERS 



567 



recalling those of ruminants. The stomach has a special sacculated 

 non-glandular chamber, presumably allowing digestion by symbionts. 

 Bettongia and other 'rat kangaroos' are terrestrial and bipedal jumpers, 

 and also have a prehensile tail (Fig. 348). 



Fig. 348. Rat kangaroo 



(Bettongia). 



(From photographs.) 



Fig. 349. Cuscus (Phalatiger). 

 (From photographs.) 



Fig. 351. Flying opossum (Petaurus). 

 (From photographs.) 



Fig. 350. Koala bear (Phascolarctos). 

 (From photographs.) 



The Australian opossums or phalangers are less modified than the 

 kangaroos and are arboreal animals, with a prehensile tail and various 

 special modifications, mostly for herbivorous diets ; Trichosurus is the 

 common phalanger, with four-cusped upper molars. Phalanger, the 

 cuscus (Fig. 349), eats mainly leaves. The koala or native bear, Phasco- 

 larctos (Fig. 350), lives on the leaves of Eucalyptus; it has cheek- 



