RODENTIA. 131 
probably as many species.* One or the other is found from Bar- 
bary to the Eastern Ocean, and as far as the north of India. 
Hetamys, F Cuv.—Pepetes, fllic.+ 
oS 
We separate from the other Jerboas, and the whole of the genus Rats, 
the Jumping Hares, which, like the Jerboas, have a large head, and great 
eyes, a long tail, and the anterior part of the body extremely small in 
comparison to the posterior, although the disproportion is much less than 
in the true Jerboas. The peculiar characters of the Helamys are four 
grinders everywhere, each one composed of two laminez; five toes to the 
fore feet, armed with long and pointed nails, and four to their great hind 
ones, all separate, even to the bones of the metatarsus, and terminated by 
large nails, almost resembling hoofs. This number of toes is the inverse 
of that most common among the rats. Their inferior incisors are trun- 
cated, and not pointed like those of the true Jerboas, and of the greater 
part of the animals comprised under the genus of rats. One species only 
is known, the 
Al. caffer.; Mus.caffer., Pall.; Dipus caffer., Gm., Buff. Supp. VI. 
xli, and better, Fred. Cuv. Mammif. It is the size of a hare, of a 
light fawn colour, and has a long tufted tail, with a black tip. In- 
habits deep burrows at the Cape of Good Hope. 
Spatax, Guldenstedt. 
The Rat-Moles have also been very properly separated from the Rats, 
although their grinders are three in number, and tuberculous, as in the 
true rats, and the hamsters, and are merely a little less unequal. Their 
incisors, however, are too large to be covered by the lips, and the extre- 
mity of the lower ones is in a sharp edge, and not pointed. Their legs 
are very short; each foot has five short toes, and as many flat and slender 
nails. Their tail is very short, or rather there is none; the same ob- 
servation applies to their external ear. They live under ground like the 
moles, raising up the earth like them, although provided with much in- 
ferior means for dividing it; but they subsist on roots only. 
S. typhus; M. typhus, Pall. Glir. pl. viii, Schreb. 206. (The 
Zemni Slepez or Blind Rat-Mole). A singular animal, whose as- 
pect is utterly misshapen by its bulky head, which is angular on its 
sides, by its short feet, by the entire absence of a tail; but, above 
all, by its possessing no eye which can be seen externally, it having 
merely under the skin a small black point, which would seem or- 
ganized for an eye, without being able however to minister to vision, 
inasmuch as the skin passes over it without either opening or be- 
coming thinner, and not having in this spot less hair than any other 
part. It is rather larger than our rat; its fur is smooth, and of an 
ash colour, bordering on a red. This is the animal, in the opinion 
of Olivier, to which the ancients alluded when they spoke of the 
mole as being perfectly blind. 
* Pallas has latterly distinguished the small Alactagas by the name of Dip. acontion. 
+ Pedetes, Jumper, Helamys, Jumping- Rat. 
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