Natural History of the Mammalia of India and Ceylon Part 69

FAMILY SPALACIDAE.

The members of this family are characterised by very large incisors; some have premolars, as in _Bathyergus_ and two other genera, but not in the _Spalacinae_, of which our bamboo-rat (_Rhizomys_) is the representative in India. "The grinding teeth are rooted, not tuberculate, but with re-entering enamel folds; infra-orbital opening moderate or small, with no perpendicular plate; occipital plane high, often sloped boldly forward; palate narrow; form cylindrical; eye and ear-conch very small, sometimes rudimentary; limbs short and stout; claws large; tail short or absent" (_Alston_, 'P. Z. S.' 1876, p. 86). There are two subfamilies--_Spalacinae_ and _Bathyerginae_.

_GENUS RHIZOMYS--THE BAMBOO-RAT_.

"Form robust; eyes very small; ears very short, naked; pollex rudimentary; tail rather short, partially haired; skull broad; occipital plane only slightly sloped forward; infra-orbital opening small, sub-triangular; upper incisors arched forward; no premolar; upper molars with one deep internal and two or more external enamel-folds; the lower molars reversed."--_Alston_.

NO. 396. RHIZOMYS BADIUS.

_The Chestnut Bamboo-Rat_ (_Jerdon's No. 201_).

NATIVE NAME.--Known to the Chingpaws or Kakhyens as the _Yewcron_.--_Anderson_.

HABITAT.--The Sikim and Nepal Terai; Burmah; Arakan; Kakhyen Hills.

[Ill.u.s.tration: _Rhizomys badius_.]

DESCRIPTION.--Fine fur, of a grey or slaty grey for two-thirds of the basal portion, the remaining upper third being from a deep to a bright chestnut. "Most intense on the head, and dullest on the rump"

(_Anderson_). "Below dark ashy grey" (_Jerdon_). "The fur of the under-parts in these Eastern examples of the species" (referring to those from the Kakhyen hills) "is paler and more reddish than chestnut, whereas in some Nepal animals it inclines even to slaty grey, washed with reddish. The area immediately around the muzzle and the chin is pale brownish, with a tinge of greyish, and the teeth are brilliant reddish, the nose, ears, feet, and tail being pale flesh-coloured" (_Anderson_, 'Anat. and Zool. Res.' p. 329).

SIZE.--Head and body, 7 inches; tail, about 2-1/2 inches.

Jerdon says of this species that "it eats the roots of bamboos and other trees, constructing burrows under the roots. It is said to be very bold, and easily taken." "In Burmah it constructs its burrows amongst a rank and tall jungle gra.s.s, on the roots of which it is said to live" (_Anderson_). Blyth, who writes of the Burmese form, says: "it is barely separable from _R. badius_, from which it seems to differ only in its much brighter colouring."

NO. 397. RHIZOMYS ERYTHROGENYS.

_The Red-cheeked Bamboo-Rat_.

HABITAT.--Burmah; the Salween hill tracts; Tena.s.serim.

DESCRIPTION.--Upper parts dark iron grey; almost black on the top of the head; the upper lip, chin and upper part of the throat are white, also the chest and belly, which are however more or less tinged with grey and reddish; the lower portion of the throat is dark grey; the sides of the head and cheeks are bright golden red; the feet are spa.r.s.ely clad and leaden coloured, except the toes of the hind feet, which are fleshy white; tail rather thick at the base, quite naked, not scaly, and of a leaden hue; claws rather broad, and moderately strong.

SIZE (of the living female).--Head and body, 14-3/4 inches; tail, 5.35 inches.

Dr. Anderson, from whose work I have taken the above description, and who was the first to describe and name this animal, says that a female was recently received in the Zoological Gardens from Mr.

A. H. Hildebrand.

NO. 398. RHIZOMYS PRUINOSUS.

_The h.o.a.ry Bamboo-Rat_.

HABITAT.--a.s.sam; very common about Cherrapoonjee; Burmah; Kakhyen hills east of Bhamo.

DESCRIPTION.--Brown above, grizzled with white; the base of the fur being slaty grey, tipped with brown, and intermixed with longer hairs, terminating in white bands; underneath much the same, only the white-tipped hairs are shorter and less numerous; whiskers dark brown; the head is generally more grey; ears, nose, feet and tail of a dusky flesh tint; tail one-third of the body.

SIZE.--Head and-body, about 11 to 13 inches; tail, 3 to 4 inches.

NO. 399. RHIZOMYS MINOR.

_The Small Bamboo-Rat_.

NATIVE NAME.--_Khai_, Aracanese.

HABITAT.--Burmah, Upper Martaban, and at Yanageen on the Irrawaddy.--_Blyth_.

DESCRIPTION.--"Dark sooty brown above, slightly tinged with deep umber, which is most distinct on the sides of the head and neck, and in reflected light; the under parts are like the upper, only the brown tint is almost absent; the whiskers are black, and tail very spa.r.s.ely haired" (_Anderson_). "Dusky brown colour, with white muzzle and around the eye, and pale naked feet" (_Blyth_).

SIZE.--Head and body, 6-1/2 inches; tail, 1-3/4 inch.

Blyth says he obtained a living specimen in Upper Martaban, and recognised it as the same as what had been obtained in Siam. The Rev.

Mr. Mason writes of it: "This animal, which burrows under old bamboo roots, resembles a marmot more than a rat; yet it has much of the rat in its habits. I one night caught a specimen gnawing a cocoa-nut, while camping out in the jungles."

I may here mention a curious little animal, which is apparently a link between the MURIDAE and the SPALACIDAE, _Myospalax fuscocapillus_, named and described by Blyth ('J. A. S. B.' xv. p.

141), found at Quetta, where it is called the "Quetta mole." A full account of it by Mr. W. T. Blanford is to be found in the 'Journal Asiatic Society of Bengal,' (vol. L. pt. ii.).

FAMILY DIPODIDAE.

This family contains a form of rodent similar to, yet more p.r.o.nounced than, the jerboa rats, of which I have already treated. It includes the true Jerboas (_Dipus_), the American Jumping Mice (_Zapus_), the _Alactaga_, and the Cape Jumping Hare (_Pedetes caffer_). The characteristics of the family are as follows:--

"Incisors compressed; premolars present or absent; grinding teeth rooted or rootless, not tuberculate, with more or fewer transverse enamel folds; skull with the brain-case short and broad; infra-orbital opening rounded, very large (often as large as the orbit); zygomatic arch slender, curved downwards; the malar ascending in front to the lachrymal in a flattened perpendicular plate; facial surface of maxillaries minutely perforated; mastoid portion of auditory bullae usually greatly developed; metatarsal bones elongated, often fused into a cannon bone; form gracile; front portion of body and fore-limbs very small; hind limbs long and strong, with from three to five digits; tail long, hairy. Three sub-families"

(_Alston_ On the Order GLIRES, 'P. Z. S.' 1876). The three sub-families are _Zapodidae_,[28] _Dipodinae_ and _Pedetinae_, but we have only to deal with the second.

[Footnote 28: Formerly _Jaculinae_.]

[Ill.u.s.tration: Dent.i.tion of Jerboa.]

_GENUS DIPUS--THE JERBOAS_.

Hind feet with three digits; tail cylindrical and tufted; incisors grooved; premolars absent, or, if found, then in the upper jaw and rudimentary; skull with very broad occipital region; greatly developed auditory bullae; the cervical vertebrae are more or less anchylosed, and the metatarsals are united. They are not found in the plains of India, though one species inhabits Yarkand, and two more are found in Eastern Persia.

[Ill.u.s.tration: _DIPUS_.]

NO. 400. DIPUS LAGOPUS.

_The Yarkand Jerboa_.

HABITAT.--Koshtak, south of Yarkand; Yarkand; and Yangihissar.--_Blanford_.

DESCRIPTION.--"Colour above light sandy brown, slightly washed with dusky, below pure white; a white band across the outside of the thigh; tail pale brown above, whitish below, with a tuft of longer hair, altogether about 2-1/2 inches long; at the end the terminal portion pure white, the proximal portion black or dark-brown on the upper part and sides, but brown or white beneath the tail. The fur is very soft and rather long, 0.6 to 0.8 inch in the middle of the back; on the upper parts it is ashy grey at the base and for the greater parts of its length, pale sandy brown near the end; the extreme tip dusky brown; on the lower parts it is white throughout; ears about half the length of the head, oval, naked inside, thinly clothed with short brown hair outside; face sandy; the hairs grey at the base; sides of head whitish; whiskers as usual very long, exceeding three inches; the uppermost brown; the longest white, except at the base; the lower entirely white; the long hairs beneath the hind feet all white, as are the feet throughout."--_Blanford_, 'Sc. Res. of Sec. Yarkand Mission,' pp. 58,59.

_GENUS ALACTAGA_.

"Hind feet with _five_ digits, of which the first and fifth do not reach the ground; tail cylindrical, tufted; skull with the occipital region less broad, and the auditory bullae smaller; infra-orbital opening with no separate ca.n.a.l for the nerve; incisors plain. One very small premolar present above only."--_Alston_.