KOALA. POTORQO. KANGAROO. RODENTIA. 75 



12. The KOALAS: Of this tribe only one species is known, 

 Koala Cinerea, which inhabits New Holland. It has a short, 

 stout body, short legs and no tail. The toes of the fore feet, five 

 in number, when about to seize any object, separate into two 

 groups ; the thumb and index on one side, and the remaining three 

 on the other. It passes one part of its life in trees, and the other 

 in burrows at their foot. 



13. The POTOROOS, Hypsiprymnm: Of this tribe only one 

 species is known. It inhabits New Holland, and is described by 

 most authors under the name of the Kanyaroo-rat. It has a long 

 powerful tail, and the two first toes of the hind feet are united as 

 in the kangaroos. It is frugivorous. 



14. The KANGAROOS, Habitat urvs, (Plate 3, fig. 11.) are 

 herbivorous animals, very remarkable for the smallness of their 

 fore paws, the length of their hind legs and tail, upon which they 

 sit vertically as on a tripod. By the assistance of these great 

 paws they leap very well, and there is one species known that can 

 clear a space of twenty feet at a single bound. The disposition 

 of the nail of the middle toe of the hind feet, makes them some- 

 what resemble ungulate mammals, for it is very large and almost 

 in the form of a hoof. They inhabit New Holland, and the 

 neighbouring Islands. One species called the Giant Kangaroo, 

 stands about six feet high. 



ORDER OF RODENTIA. 



15. The RODENTIA or gnawers, are easily distinguished from all 

 other unguiculate mammals without mammary pouches, by the 

 arrangement of their teeth, which correspond to the nature of 

 their food. These animals have no canine teeth, and there is a 

 vacant space between the incisor and molar teeth. (Plate 4 fig. 6.) 

 The first are remarkable for their strength, their length, their 

 arched form, and the lozenge shape of their cutting edge ; their 

 number is almost always two in each jaw, and their anterior 

 surface is ordinarily tinged, of a more or less deep yellow colour. 

 The molar teeth have a large, flat crown, traversed by raised 



12. What are Koalas ? 



13. What are Potoroos ? 



14. What are Kangaroos ? To what pnrt of the world do they belong ? 



15. How are the Rodentia distinguished? What are the cha acters of 

 their canine teeth ? What is their number ? What is the co'our of the 

 canine teeth? What are the characteis of the molar teeth of gnawers? 

 How is the lower jaw attached to the cranium ? What circumstance has 

 given the name to this order of animals ? 



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