426 



VERTEBRATA. 





.gS^ 



HEAD OF HEI.IOPHOBirS. 



swim well. The species are not only exceedingly numerous, but very generally distributed in all 

 parts of the world; some arc even indigenous to Australia. Under this head we shall first notice 

 the tribe of Rat-Moles, and then the Muriens, of which the principal types are the Field-mice and 

 common Rats and d//ce. 



THE RAT-MOLES. 



This tribe arc all burrowcrs, have a large head, the 

 tail short or altogether wanting, and the eyes very small. 

 There are several genera, as Bathyergus, Georychu^ 

 Rhizomys, Siphneus, Spalax,an6 ETeliophobius. 



Genus HEUOPHOBIUS : Eeliophobius.— Of this 

 there is a single species, H. argenteus, which is the only 

 one of the Rodcntia which has five pairs of molars in each 

 jaw. It is little known beyond its appearance; it is of a 

 silver-gray color, and has a head and feet not easily de- 

 scribed, and of which we therefore present engravings. 



Genus BATHYER< JUS : Bathyergus. — These animals, 

 belonging to Africa, have no external ears; they have 

 extremely small eyes, a short tail, and a squat body ; 

 they burrow and form galleries, like the moles, in sandy 

 wastes, generally near the sea. These are the proper 

 Rat-moles. There are several species, as follows : 



The Coast Rat, or Cape Mole, the Great Cape Mole 

 of Buffon, the Zand Moll of the Dutch, and Kauw- 

 Houba of the Hottentots, B. mariiimus, is nearly the 

 size of a rabbit, being thirteen inches long, and its tail a 

 little more than one inch. It perforates the earth with 

 its long, horizontal galleries in such a manner that 

 persons often break into them and sink up to their 

 knees, and rendering it exceedingly dangerous to ride 

 among them. It lives on roots and bulbs, and is found 

 in the region of the Cape of Good Hope, especially in 

 the sand-flats near the sea. It is of a reddish-gray color. 

 The Hottentot Bathyergus is of a brownish-gray, 

 and is half the size of the preceding; this also is found 

 near the Cape. Two other undescribed species are men- 

 tioned by naturalists: one is called B. Buffonii ; the 

 other is yet unnamed. 



Genus GEORYCIIUS : Georychus.—Oi this then 

 a single species, the G. Capensis; this is five inches long, 

 with a tail two-thirds of an inch. It lives in burrows, 

 and generally resembles the Bathyergus. It is found in 

 South Africa. 



There are several species of field-mice, arranged under 

 this genus by some authors, which we shall notice under the head of Lemmings. 



Genus RHIZOMYS: Rhizomys. — These animals have a long body, small eyes, and short 

 tails, and resemble the rat-moles. A single species only is well known, the Bamboo-Rat, 

 R. Surnatrensis, the body of which is thirteen or fourteen inches long, and the tail fivi I 

 the general color is a light yellowish-gray; it has been erroneously referred to Sumatra M^ 

 .lava; its true habitat is in the dense and almost impenetrable bamboo thickets of Mai* 

 It feeds on tin' young roots of that plant, and on various fruits. It lives in burrows, from which 

 it only issues at night. This animal is described by Temminck under the - name of the Decern- 

 Nyctocle, tes, and is probably the same as the R. Chincnsis of Gray. The Mus talpinus, of Pallas; 



FACE OF IIELIOPHOB1US. 



FEET of ni-a.iopnonirs. 



