CHAPTER  XX3rr 
RopENTS,— continued. 
THE MousE-LikE RODENTS. 
Families MvoxID2Z, MurRIDZ, SPALACIDA, ete. 
THE Rodents treated of in the present chapter comprise several families more or 
less closely related to the rats and mice, and hence collectively termed the mouse- 
like group. They differ from the squirrel-like Rodents described in the preceding 
chapter in the following points. In the first place, as shown in the accompanying 
figure of the skeleton of the dormouse, 
the two bones of the lower leg (tibia and 
fibula) are united at their extremities. 
Secondly, in the slender zygomatic or 
cheek-arch of the skull, the cheek-bone 
(jugal) seldom extends far forwards, and 
is usually supported from below by a long 
process from the upper jawbone (maxilla). 
None of them have any _postorbital 
SKELETON AND MOLARS OF COMMON DORMOUSE. — processes in the skull marking the hinder 
boundary of the upper part of the eye- 
sockets, and in no ease is there more than a single pair of premolar teeth in each 
jaw, while frequently even these may be wanting in either one or both jaws. 



ALi. Pn 
p Sito 
Nay Oy” 
Tae 
THE DORMICE. 
Family MYoXxIDz. 
The elegant little creatures known as dormice, or sleepers, so closely resemble 
diminutive squirrels in form and habits, that they are commonly regarded as closely 
allied to that group. Apparently, however, these external resemblances are solely 
due to adaptation to a similar mode of life, the relationship of the dormice to the 
true mice being much closer than it is to the squirrels. 
The dormice are confined to Europe, Asia (exclusive of the Indian and Malayan 
regions), and Africa, and are all of small size and arboreal habits. They are 
characterised by their large ears and eyes, and long, thickly-haired tails, the fore- 
limbs being short in proportion to the hinder ones. There is a pair of premolar 
teeth in both jaws, so that the total number of cheek-teeth on each side is four; 
