MURIDE 475 
predaceous habits, omnivorous diet, and great fecundity. They 
bear four or five times in the year from four to ten blind and 
naked young, which are in their turn able to breed at an age of 
about six months; the time of gestation being about twenty 
days. 
The Black Rat (Jf rattus) is a smaller and more lightly built 
species, generally not more than 7 inches in length, with a slender 
head (Fig. 212, B), large ears, and a thin tail of about 8 or 9 
inches in length. The colour is usually a glossy bluish-black, some- 
what lighter below; but in the tropical variety described as MM. 
alecandrinus the general colour is gray or rufous, and the belly 
white. The disposition of the Black Rat is milder than that of 
AM. decumanus, and the white and pied rats kept as pets mostly belong 
to this species. In many localities where it was formerly abundant 
it has been entirely superseded by Af: decumanus, but it is said that 
in some parts of Germany it has been lately reasserting itself. 
M. musculus, the Common House-Mouse, is, like the Brown Rat, 
originally a native of Asia, whence it has spread to all the inhabited 
parts of the globe. Its habits and appearance are too well known 
to need any description. 
M. sylvaticus, the Wood or Long-tailed Field-Mouse, is very 
common in many parts of England, often taking to barns and out- 
houses for shelter during the winter. It is of about the same size 
and proportions as J/. musculus, but of a bright reddish-gray colour, 
with a pure white belly. 
M. minutus, the Harvest-Mouse, is the smallest of the European 
Mice, seldom exceeding 24 or 3 inches in length. It is of a 
yellowish-red colour, with comparatively short ears and tail. It 
lives entirely away from human habitations, generally dwelling in 
grass or corn-fields, where it builds a globular nest of dried grass of 
the size of a cricket-ball, in which the young are nurtured. 
Nesocia.1—General characters those of Mus, but the incisors 
and molars very much wider, and the tubercles of the latter more 
connected by transverse ridges, thus producing a laminated type 
of structure. 
This genus has been placed by some writers in a distinct sub- 
family with Phileomys, but Mr. O. Thomas regards it as so closely 
allied to Mus that even its generic separation may be open to 
question. It comprises several species, mostly spread over Southern 
Asia, ranging from Palestine to Formosa, and from Kashmir to 
Ceylon, but N. scudlyi is found in Turkestan. The great Indian 
Bandicoot-Rat (NV. bandicota) is the largest representative of the 
subfamily, often exceeding a foot in length. N. bengalensis is 
remarkable for possessing no less than eighteen mamme. Fossil 
remains of Nesocia occur in the Pleistocene of Madras and in the 
1 Gray, Ann. Mag. Nat. Hist. vol. x. p. 264 (1842). Amended from Nesokia. 
