i 5 6 



MARSUPIAL! A 



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 Pkascolomyidce. 1 



Phascolarctus. 2 — Dentition: i%, c^,%> \, m±; total 30. Upper 

 incisors crowded together, cylindroidal, the first much larger than 

 the others, with a bevelled cutting 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 Pseudochiriis. The loAver 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 Avith 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. Xo external 

 tail. Fur dense and woolly. 

 Ears of moderate size, thickly 

 clothed with long hairs. Verte- 

 bras : C 7, D 11, L8, S2, C8. 

 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 

 the Australian colonists (P. cin- 

 ' r< us), an animal of compar- 

 atively large size and heavy 

 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 Cf. W. A. Forbes, "Anatomy of the Koala," Proc. Zool. Soc. 1881, p. 180. 

 - Blainville, Bull. Soe. Philom. 1816, p. 116. 



f Fig. 4 1 .'.— Skeleton of right hind foot of Koala 

 (I'hascolarctus cinereus), showing the stout op- 

 posable hallux, followed by two slender toes, 

 which in the living animal are enclosed as far 

 as the nails in a common integument. 



