THE MOUSE TRIBE. 117 



dwell together; and is thoroughly nocturnal. At the Cape it is found in consider- 

 able numbers, and frequents both the mountains and the open plains. When 

 feeding, the jumping hare goes on all fours: but when at speed progresses with 

 the leaps characteristic of the family. Ordinarily the length of each spring is from 

 six to nine feet; but it is said that the hap may occasionally- cover a space of as 

 much as twenty or even thirty feet. The young are born during the African 

 summer, and are usually from three to four in number; and during the rainy 

 season young and old alike seldom stir from their burrows. The food appears to 

 be entirely of a vegetable nature. The flesh is largely eaten by the Hottentots, 

 who catch almost as many of the creatures as they please by the simple expedient 

 of pouring water down their holes, upon which the owners immediately bolt. 



The Smintih & 



Genus Sminthus. 



Three rat-like Rodents — the one {Sminthus svbtilis) from Eastern and 

 Northern Europe and Central Asia, the other (S. concolor) from North -Western 

 China, and the third (S. leathami) from Kashmir — are interesting in showing that 

 the long hind-limbs are not an essential attribute of the members of the present 

 family. Indeed the former of these Rodents — for which there is unfortunately no 

 English name — is so rat-like in appearance that it was long referred to the next 

 family. It differs, however, from all the members of the latter by the presence of 

 .:* pair of premolar teeth in the upper jaw (although there are none in the lower), 

 while its skull agrees in essentia] features with that of the jerboas. The common 

 sminthus has rather long and pointed ears, and a tail of nearly the same length as 

 the body, and clothed with short hairs. The premolar and last upper molar teeth 

 are very small; and the whole of the cheek-teeth have a complex pattern on 

 their crowns. 



The Mouse Tribe. 



Family Mrr.ii'.i:. 



The Mouse family, which includes mice. rats, hamsters, voles, lemmings, etc., is 

 by far the most extensive group in the whole Rodent order, having a cosmopolitan 

 distribution, and being the only family represented in Australia. The majority of 

 the mice — as we may conveniently term all the members of the group — are of 

 terrestrial habits, and have naked and scaly tails of varying length ; while in most 

 cases there is no great disproportion between the length of the fore and hind-limbs. 

 The incisor teeth are narrow ; and, owing to the invariable absence of premolars, 

 there are never more than three pairs of cheek-teeth in each jaw. 



In structure these teeth exhibit great variation in the different groups, being- 

 either furnished with roots, or rootless, while in some cases their crowns are 

 surmounted with simple cusps, and in others with folds of enamel arranged in a 

 series of angles. In all cases the first toe of the fore-foot is rudimental. The skull 

 is the most characteristic part of their entire organisation, although it is difficult 



