THE LIVING WORLD. 
507 
The Mexican Pouched Rat, or Gopher (G . mexicanus ), is larger than the 
chestnut-cheeked gopher, being about eleven inches long. It is darker, too, its 
color approaching black. 
The Jerboa, or Bush-tailed Kangaroo (Bettongia penicillata ), is about the 
size of an .English hare, is nocturnal in its habits, and specially clever in try¬ 
ing, like a true Briton, to hedge himself off from everything but “his majesty, 
himself.” When grass is short and scanty, or the hillside devoid of herbage, 
the jerboa confronts the architectural problem of how, with insufficient mate¬ 
rial, to build a domicile, such as its instinct teaches it that it should have. 
He meets the difficulty by going elsewhere in search of building material, and 
having found it, collects the grass into little hay-ricks or sheaves, which he 
grasps with his prehensile tail, and then skips along to the site selected. As 
long as the young occupy the nest, the fond and careful parent never leaves 
or comes into her house without carefully concealing the entrance-way. It is 
to be borne in mind that, in the case of the jerboa , as in so many others, the 
popular appellation is no 
indication of family, as de¬ 
termined by anatomical 
structure; for the jerboa is 
no kangaroo at all, but a 
member of the rodentia. 
The African Petromys 
{Petromys typicus ), or Rock- 
rat, is found in south-west¬ 
ern Africa, in the valley of 
the Orange river. It is about 
seven inches in length with 
a tail yearly as long as the 
body. It is of a reddish 
color, and though the hind 
legs are not disproportion¬ 
ately developed, walks upon them, instead of going upon all four, 
nest among piles of stones, or in the crevices of rocks. 
The Dormouse (Muscardinus avellanarius ), or Mus Avellananus ( Lin - 
nceus ), a beautiful little animal, is very intimately allied to the squirrels, among 
which it has been placed by some authors, from which it differs chiefly in 
wanting the anterior, small molar in the upper jaw; in having the tail less 
bushy, and the hind legs less elongated. Its form is compact and full, the neck 
short, the head rather large, the nose prominent, the eyes of moderate size, the 
ears rather short and broadly rounded, the feet of delicate structure. The gen¬ 
eral color is light, yellowish-red, gradually becoming paler beneath, the fore part 
of the neck nearly white, the tail dull red. It is about five inches long. 
In its habits the dormouse resembles the squirrel, inasmuch as it climbs 
with facility, and exhibits great liveliness and agility; but it is also allied to 
the mouse, and passes a great part of its time on the ground, feeding on grass, 
corn and various small fruits. It resides in thickets generally remote from 
human habitations, placing its nest in bushes, and forming it of grass and 
leaves, intricately interlaced, and disposed in a roundish form with a narrow 
aperture at the top. Having laid up a store of food, and, like other hibernating 
jerboa (Dipus frjrypticus). 
It builds its 
