grees in size with _A. Hemachalanus_ it differs considerably
in colour, and, according to Mr. Blanford, also in the skull. There
is a beautifully drawn and coloured plate of this marmot in the work
from which I have just quoted; also of _A. Himalayanus_ and _A.
caudatus_.

NO. 314. ARCTOMYS DICHROUS.

HABITAT.--Afghanistan; mountainous country north of Cabul.

DESCRIPTION.--Less yellow than the last, without any black on the
back, and having the upper parts pale dull tawny, and the lower rufous
brown. The tail concolorous with the belly, tinged here and there
with rich rufous brown, the tip paling to nearly yellowish-brown.

SIZE.--Head and body, 17 inches; tail, 6-1/2 inches.--_Anderson_,
'Ann. and Mag. Nat. Hist.,' vol. xvi. 1875.

NO. 315. ARCTOMYS ROBUSTUS.

Is a Thibetan species, described by Prof. Milne-Edwards, 'Recherches
sur les Mammiferes,' p. 309. I have not the work by me just now.

SECTION II.--MYOMORPHA--RAT-LIKE RODENTS.

The second section of the order GLIRES, containing the following
families--those that are not Indian being in italics:--

_Myoxidiae_, _Lophiomyidae_, Muridae, Spalacidae, _Geomyidae_,
_Theridomyidae_ (fossil), Dipodidae.

The molar dentition is from 3--3/3--3 to 6--6/6--6, the former being
the usual number; the tibia and fibula are united for at least a third
of their length; the zygomatic arch is slender, and the malar process
rarely extends so far forwards as in the preceding section, and is
generally supported below by a continuation of the maxillary
zygomatic process; the collar-bones are perfect (except in
_Lophiomyidae_). Upper lip cleft; the muffle small and naked; tail
cylindrical, sometimes hairy, but commonly covered with scales
arranged in rings.

In all the Indian mammalogy this section is probably the most
difficult to write about. Our knowledge of the smaller rodents is
extremely imperfect, and is just engaging increased attention. In
the meanwhile I feel that, while I make use of such material as is
now available, before long much will have to be revised and corrected
after the exhaustive inquiries now being made by Dr. Anderson are
published.

The Indian families with which we have to deal are but three--the
_Muridae_, _Spalacidae_, and the _Dipodidae_. The _Arvicolidae_ of
Jerdon's work is merely a sub-family of _Muridae_. Of these the
_Muridae_ take the first place, as containing the greater number of
genera. It is estimated that the total number