Part 19

In. Lines. Length from nose to root of tail 3 6 of tail 1 7½ from nose to ear 0 10 of tarsus (claws included) 0 9 of ear 0 3¾

Habitat, Hardy Peninsula, Tierra del Fuego, (February.)

The white, which is usually confined to the under parts of the body, in this species extends slightly on the sides of the body, and the lower portion of the cheeks.

“This species was caught on the mountains, thickly covered with peat, of Hardy Peninsula, which forms the extreme southern point of Tierra del Fuego.”—D.

17. MUS CANESCENS.

Mus canescens, Waterh., Proceedings of the Zoological Society of London for February, 1837, p. 17.

M. suprà canescens, subtùs albus; oculis flavido cinctis; auribus parvulis, pilis pallidè flavis et plumbeis obsitis; mystacibus mediocribus, canis, ad basin nigricantibus; caudâ vix corpore breviore, suprà fusco-nigrâ, subtùs sordidè albâ; pedibus anticis tarsisque flavescentibus.

DESCRIPTION.—Fur moderately long and loose; ears small; tail nearly equal to the body in length: general colour gray, with a wash of very pale yellow; chin, throat, and under parts of the body, white. Tail tolerably well clothed with hairs, those on the upper surface brown, and those on the under, whitish; on the sides are some yellowish hairs. Ears with yellow hairs on the inner side; tarsi pale yellow, toes white; muzzle and around the eye yellowish.

In. Lines. Length from nose to root of tail 3 6 of tail 2 1 from nose to ear 1 1 of tarsus (claws included) 0 9½ of ear 0 4

Habitat, Santa Cruz and Port Desire, (December.)

“Very common in long dry grass in the valleys of Port Desire.”—D.

The skull is figured in Plate 33, fig. 5, c. Fig. 5, a. represents the molars of the upper jaw; fig. 5, b. those of the under jaw, and fig. 5, d. represents the posterior molar of the under jaw when more worn.

It was with some hesitation that I described this as a distinct species in the Society’s Proceedings. I have now re-examined the specimens, and still am unable to satisfy myself whether they are varieties of Mus xanthorhinus or not. Both of Mus canescens and of Mus xanthorhinus, I have before me what I imagine to be an adult and a young specimen. The adult and the young of M. xanthorhinus agree in being of a yellowish brown colour, and in having the muzzle and tarsi deep yellow; both specimens of Mus canescens are of a gray colour, with an indistinct yellow wash, the muzzle and tarsi being tinted with yellow, as in M. xanthorhinus. Besides this difference in tint, which, perhaps, is unimportant, M. canescens differs from M. xanthorhinus in having the head larger, the tail rather longer, and the fur less soft. The specimens of this animal are both from Patagonia; one of the specimens of Mus xanthorhinus was brought by Mr. Darwin from Terra del Fuego; and as the other formed part of Captain King’s collection, it in all probability came from the same locality. As I only possess one skull, I cannot speak with certainty as regards the size of the head; the difference, however, in the stuffed specimens is considerable, and it is strange that each of the pairs should agree so perfectly, supposing the difference to be the work of the stuffer’s hands.

18. MUS LONGIPILIS. PLATE XVI.

Mus longipilis, Waterh., Proceedings of the Zoological Society of London for February 1837, p. 16.

M. suprà obscurè griseus, flavo lavatus; subtùs griseus; pedibus fuscis, unguibus longiusculis; auribus mediocribus; caudâ corpore breviore, suprà nigrescente, subtùs fuscescente; rhinario sub-producto: vellere longissimo, molli.

DESCRIPTION.—Fur very soft and silky, and extremely long—the ordinary fur of the back measuring nearly three quarters of an inch, and the longer hairs one inch in length; ears moderate; tail nearly as long as the body; muzzle much pointed; general colour gray, washed with yellow, the under parts pale gray, or grayish white; feet brown; ears and tail well clothed; the hairs on the inner side of the ears are chiefly of a yellow colour, those on the upper surface of the tail are brown-black, those on the under part are dirty white; the hairs of the back are deep gray at the base, broadly annulated with yellow near the apex, and dusky at the apex; the longer hairs are grayish black; the hairs of the moustaches are dusky at the base, and whitish beyond that part; the claws are long, and but slightly curved; the incisors are slender; those on the upper jaw are yellow, and those of the under yellow-white.

In. Lines. Length from nose to root of tail 5 4 of tail 3 4 from nose to ear 1 2 of tarsus (claws included) 1 0½ of ear 0 6½

Habitat, Coquimbo, Chile, (May.)

This mouse is remarkable for the great length and softness of its fur, even among the species here described, most of which have very loose, long and soft fur.

The molars of the upper jaw are figured in Plate 33, fig. 6, b.—molars of the lower jaw, fig. 6, a.

“Inhabits dry stony places, which character of country is general in this part of Chile.”—D.

19. MUS NASUTUS. PLATE XVII.—Fig. 2.

Mus nasutus, Waterh., Proceedings of the Zoological Society of London for February 1837, p. 16.

M. suprà obscurè flavescenti-fuscus, ad latera fulvescens; subtùs obscurè fulvo tinctus: pedibus pilis obscurè fuscis tectis; unguibus longis; auribus mediocribus; caudâ corpore breviore, suprà fuscá, subtùs sordidè albâ: rhinario producto.

DESCRIPTION.—Muzzle very long and pointed, ears small, tail shorter than the body, claws long and but slightly arched; inner, rudimentary toe of the fore foot furnished with a pointed claw; fur moderate, and slightly glossy: general colour yellowish brown, of the sides of the body yellow, of the under parts pale yellow; the chin, throat and chest whitish: feet brown; ears well clothed with hairs, those on the inner side are most of them yellow, but some are black. All the fur is of a deep lead colour at the base; the hairs on the upper parts and sides of the head and body are broadly annulated with deep golden yellow near the apex, and blackish at the apex; on the upper parts long brownish black hairs are thickly interspersed with the ordinary fur, but on the side of the body they are less numerous, hence on this part the yellow tint prevails; on the under parts of the body the hairs are broadly tipped with pale yellow, and in parts with white: the tail is but sparingly clothed with hairs, those on the upper surface are of a dark brown colour, and those on the under are pale brown. The incisors are very slender and of a very pale yellow colour.

In. Lines. Length from nose to root of tail 5 2 of tail 2 8 from nose to ear 1 3 of tarsus (claws included) 1 0½ of ear 0 5

Habitat, Maldonado, La Plata, (June.)