156 JLARSUPIALIA 
between the first lower incisor and fourth premolar. Tongue 
of ordinary structure. Distinct cheek-pouches. Stomach with a 
special gland near the cardiac orifice. Caecum very long, and (with 
the upper portion of the colon) dilated and provided with numerous 
longitudinal folds of mucous membrane. In many anatomical 
characters, especially the possession of a special gastric gland, this 
group resembles the Phascolomyide.1 
Phascolarctus.2—Dentition : 12, ¢4, p+, m4; total 30. Upper 
incisors crowded together, cylindroidal, the first much larger than 
the others, with a bevelled eutting edge (Fig. 36). Canine very 
small ; a considerable interval between it and the premolar, which 
is as long from before backwards but not so broad as the true 
molars, and has a cutting edge, with a smaller parallel inner ridge. 
The molars slightly diminishing in size from the first to the fourth, 
with square crowns, each bearing four pyramidal cusps, with curved 
ridges radiating from them, and having a structure very similar to 
these of Pseudochirus. The lower incisors are semiproclivous, com- 
pressed and tapering, bevelled at the ends. Premolars and molars 
in continuous series, as in the upper jaw. Milk-tooth very minute, 
and almost functionless. Fore feet with the two inner toes slightly 
separated from and opposable to the remaining three, all with strong, 
curved, and much compressed 
claws. Hind foot (Fig. 49) with 
the hallux placed very far back, 
large and broad, the second and 
third (united) toes considerably 
smaller than the other two ; the 
fourth the largest. No external 
tail. Fur dense and woolly. 
Ears of moderate size, thickly 
clothed with long hairs. Verte- 
bre: C7,D11,L8,82, Cs. 
Ribs eleven pairs, a rare excep- 
tion to the usual number (13) 
in the Marsupialia. 
There is but one species, 
the Koala or Native Bear of 
£Fic. 49,—Skeleton of right hind foot of Koala the Australian colonists (P. cin- 
(Phascolarctus cinereus), showing the stout op- @réus), an animal of compar- 
posable hallux, followed by two slender toes, atively large size and heavy 
which in the living animal are enclosed as far * . ie 4 
as the nails in a common integument. build (Fig. 50), found in the 
; ; ; south-eastern parts of the Aus- 
tralian continent. It is about two feet in length, and of an ash- 
gray colour, an excellent climber, and residing generally in lofty 
1 cy, W. A, Forbes, ‘ Anatomy of the Koala,” Proc. Zool. Soc. 1881, p. 180 
? Blainville, Bull. Soc. Philom, 1816, p. 116. 
