498 



Vertehrata. 



membrane ; the hallux is wanting or rudimentary, i ^. ' Whilst in other 

 Marsupials the fore limb has five well-developed digits, in one of the two 

 genera of Bandicoots (Peraineles) the first and fifth fingers are very degenerate 

 and destitute of claws, in the other (Chceropus) they are completely absent, 

 and the fourth has also become rudimentary. In the True Bandicoot 

 (Perameles), a rudiment of the hallux is present, the fourth is the best developed 

 toe; in the Pig-footed Bandicoot {Cliceropus) (Fig. 403 c), the rudiment 

 of the hallux is wanting, and the second, third, and fifth are veiy thin, almost 

 rudimentary. 



3. Kangaroos (Diprotodontia) have usually three incisor teeth in the 

 upper, one in the lower jaw. The canines are absent or small, the molars with 

 rough cusps or transverse ridges. Of the toes of the hind foot the second and 

 third ^re weaker than the fourth or fifth, and are surrounded by a common 

 membrane (syndactylous). Herbivorous. 



(a) Australian Opossums (Phalangistidss). The hind, are little 

 longer than the fore, limbs. Hallux well-developed, without a claw ; opposable 

 (Fig. 403 A), i \. Climbing animals. The following may be noted: the 



Fig. 403. Right hind foot: A of Phalangista, B of the Kangaroo, C of 

 Choeropus. a astragalus, c calcaneum, n centrale (naviculare), c' — c^ cuneiforms, cb cuboid 

 I—Y first to fifth toes. — After Flower. 



C u s c u s {Phdlangista), with long prehensile tail : the Plying Phalangers 

 (Petawrus), with a large membrane (patagium) stretched between the fore and 

 hind limbs : the Koala or Australian Bear {Phascolarctos), a clumsy 

 ecaudate creature ; in which the fingers, like those of the Chameleon, are united 

 in two bundles (the first and second may be opposed against the third, foui'th, 

 and fifth): and the small, aberrant, insectivorous, Long-snouted Pha- 

 lange r (Tarsipes) with long protrusible tongue; few rudimentary molars (|) ; 

 and rudimentary claws on all the fingers and toes with the exception of the 

 second and third toes of the hind foot. 



(6) Kangaroos (Macropodidse). Hind legs very long, adapted for 

 jumping; hallux absent; toes, second and third, very thin, fourth and fifth, 



