78 LLOYD S NATURAL HISTORY. 
gers, like their analogues the Flying Squirrels, have developed 
their parachutes, independently of one another, from distinct 
groups of their non-volant cousins. In the case of the three 
genera of the flying forms, this is proved by the circum- 
stance that while their relationship to one another is of the 
most distant nature, each is closely allied to a non-flying 
genus. 
While the great majority of the members of the family are 
purely vegetable feeders, subsisting chiefly on leaves and fruits, 
a few feed either entirely or partially on insects, while others 
have taken to a diet of flesh. 
THE KOALAS. GENUS PHASCOLARCTUS. 
Phascolarctos, Bainville, Bull. Soc. Philom., 1816, p. 110. 
The genus Phascolarctus, which is represented by a single 
Australian species, is also the type of the first sub-family 
(Phascolarctine), the distinctive characters of which are as 
follows :— 
Tail- wanting ; muzzle short and broad ; tongue not extensile ; 
cheeks furnished with pouches ; intestine with a blind appen- 
dage, or cecum; teeth large ; only one premolar in the upper 
jaw. . 
The genus itself may be defined by the following assemblage 
or - characters <— 
Size large; form very stout and clumsy; fur thick and woolly ; 
ears large and thickly furred ; fore toes sub-equal, their relative 
lengths in the order 4, 3, 5, 2; 1; and the first. and second op- 
posable to the rest ; claws thick, strong, and sharp ; soles of 
both pairs of feet granulated, without striated pads. Two teats ; 
eleven pairs of ribs. Upper molar teeth with low squared 
crowns, carrying curved crests, of which the convexity is turned 
outwards. 
