The sixth specimen, which is from Maldonado, is considerably less than British specimens of the common mouse, and is of a richer and brighter colour, the head is smaller, the muzzle shorter in proportion, whilst the tarsi are even longer than in a large specimen of M. Musculus. These points of dissimilarity induced me to believe it was a distinct species, and to apply to it the specific name of brevirostris.[[17]] Upon re-examination, with the advantage of more experience, and consequently a better knowledge of the characters of these animals, I have changed my opinion. The teeth indicate that it is not an adult specimen, and agree perfectly with those of M. Musculus, both in form and size. “Common in the houses of the town of Maldonado, and its habits are similar to those of Mus Musculus.”—D.
6. Mus longicaudatus.
Plate XI.
Mus longicaudatus, Bennett, Proceedings of the Committee of Science and Correspondence of the Zoological Society of London for January, 1832, p. 2.
M. pallidè flavescenti-fuscus; corpore subtùs albo, levitèr flavo lavato; pedibus albis; tarsis permagnis; caudâ perlongâ; auribus parvulis.
Description.—Fur long and soft; general colour pale yellow-brown, the hairs of the ordinary fur being fulvous near the apex, and the longer hairs brown. On the sides of the body, cheeks, and external side of limbs, the fulvous hue prevails. The inner side of the limbs and the under parts of the body are white, but have an indistinct yellowish hue. All the hairs of the body are of a deep gray colour at the base. The ears are small, well clothed with hairs; those on the inner side are chiefly yellow; externally, on the fore part they are brown, and posteriorly whitish. The feet are of a flesh-colour, and furnished above with white hairs; the tarsi are but sparingly provided with minute hairs on the upper side, and are naked beneath: they are of unusually large size. The fore feet are of moderate[[18]] size, and furnished with a very large carpal tubercle. The tail is very nearly double the length of the body, if the latter be measured in a straight line; it is of a brownish flesh-colour above, paler beneath, and sparingly furnished with minute bristly hairs; those on the upper surface being brown, and on the under side white. The hairs of the moustaches are long, of a black colour, and grayish at the apex.
| In. | Lines. | ||
|---|---|---|---|
| Length | from nose to root of tail | 3 | 9 |
| of tail | 5 | 3 | |
| from nose to ear | 0 | 10½ | |
| of tarsus (claws included) | 1 | 1 | |
| of ear | 0 | 4 |
Habitat, Chile.
The most conspicuous characters of the present species consist in the immense length of the tail, and the great size of the hinder feet.[[19]] It is about equal in size to Mus Musculus; its form, however, is somewhat stouter; in colour it is much paler and brighter. The head is larger in proportion; the ears are smaller, and more densely clothed with hair; the fore feet are rather larger, and the fleshy tubercle on the under side of the wrist is also larger. The thumb nail is flattened, and rounded at the tip, as in Mus Musculus, but is longer, and more distinct than in that animal.
The skull of M. longicaudatus, (Plate 34, Fig. 1,) is considerably larger than that of the common mouse, but in form scarcely differs from it; its upper surface is rather more convex, and the interparietal bone proportionately less. The length of the skull is 1 inch; breadth, 6½ lines; distance between the forepart of the incisor, and the first molar of the upper jaw, 3½ lines. The dentition is figured in Plate 34, Figs. 1. b and 1. c.
The above account is drawn up from the same specimen as that from which Mr. Bennett took his description, and which was brought from Chile by Mr. Cuming, who states that the animal in question lives in trees, and constructs its nest with grass.