Part 13

Chirogale trichotis, Forsyth Major, Nov. Zool., vol. i., p. 26 (1894).

PLATE V.

{53}CHARACTERS.--Brownish-grey above; lower parts grey with the hairs white-tipped; a spot in front of the eye black; the lips and a line down the nose, white. Hands and feet grey, the hairs white-tipped. Ears short, concealed in fur, with tufts of long hair on the lower part and on the space in front of the ears. Tail shorter than the body, its hair short except forwards, where it is longer.

Skull depressed and flattened; cranial portion short.

DISTRIBUTION.--The only known specimen of this species is the type in the British Museum, obtained by Crossley during his journey from Tamatave to Mouroundava.

IV. CROSSLEY'S MOUSE-LEMUR. CHIROGALE CROSSLEYI.

Chirogaleus crossleyi, Grandid., Rev. et Mag. de Zool., xxii., p. 49 (1870).

CHARACTERS.--Smaller than C. melanotis (Major); tail short and very hairy. Head very large, rounded; ears small and haired. Hind-limbs longer than fore. Upper side, especially the head, rufous; under side greyish-white. Round the eyes a black ring; inner aspect of the ears dark brown, the upper border black. (Grandidier.)

Length, 8 inches; tail, 4¾ inches.

DISTRIBUTION.--Crossley's Mouse-Lemur is known as yet only from the forests to the east of Antsianak, in Madagascar.

HABITS.--The two species last described (Chirogale trichotis and C. crossleyi) are very closely related together. They are nocturnal animals, and very rare; consequently but little is known of their habits. It is, however, very improbable that they depart widely from those of the better known Mouse-Lemurs.

{54}THE DWARF-LEMURS. GENUS MICROCEBUS.

Microcebus, Geoffr., Cours de l'Hist. Nat., Mamm., leçon vi., p. 24 (1828).

Under this genus are arranged five species of very small Lemurs, whose hind-limbs are longer than their fore-, though less so in proportion than is the case among the African Galagos. Their snout is also shorter; their eyes are large, approximated together, very prominent and very bright, and their ears are elongated. On the ventral surface are situated four mammæ, two on the breast and two on the abdomen.

Of their bony framework, the brain-case is high, broad, and more vaulted than that of either the Mouse-Lemurs or the species of the next genus, Opolemur. The facial region is also shorter. The mastoid portion of the ear-capsules (periotic bones) and the squamosal region is somewhat less inflated than in Galago. With regard to their dentition, the inner upper incisor is larger than its outer fellow. Between the upper canine and the anterior pre-molar of its own side there exists no gap, nor is there a space between the anterior and the median upper pre-molars. The molars have three-cusped crowns, but these cusps are very sharp, and are weaker than those in Galago; the intermediate cusp between the two main cusps to the front is wanting. The concavity also of the hinder margin (so marked in Galago) is here very slight, but the basal ring (cingulum) is swollen internally to form an inner hind cusp. The posterior upper molar is smaller than the anterior, and its inner hind cusp is rudimentary. The hind border of the bony palate extends to behind the last molar tooth, its posterior perforations being very large. The angle of the lower jaw is not produced downwards.

{55}The foot in the Dwarf-Lemurs is long, on account of the elongation of two of its ankle-bones (the cuboid and the naviculare).

The species of this genus are confined to the island of Madagascar. They are entirely nocturnal, as their large eyes and inflated ear-capsules might suggest. They are chiefly arboreal and frugivorous.

I. SMALL DWARF-LEMUR. MICROCEBUS MINOR.

Microcebus murinus, Martin, P. Z. S., 1835, pp. 125.

Galago minor, Gray, Ann. and Mag. N. H., x., p. 255 (1842).

? Chirogalus gliroides, Grandid., C. R., 14 Dec., 1868.

Chirogaleus pusillus, Flower and Lydekker, Mammalia, p. 690 (1891 partim).

Microcebus minor, Forsyth Major, Nov. Zool., vol. i., p. 8 (1894), Taf. i., fig. 2; ii., figs. 5-7, 14, 15 (with full synonymy).

CHARACTERS.--Head rounded; muzzle short and pointed; eyes large and brilliant; ears large and naked; tail longer than body. Length of body, 5 inches; of tail, 6 inches.

Upper side, either for the most part Mouse-grey, washed with light rufous-brown, with the stripe down the back more or less distinct and somewhat darker; or with the rufous-brown colour preponderating. In grey specimens the upper side of the tail is washed with rufous, the under side being somewhat lighter. Cheeks, throat, breast, belly, and inner side of limbs almost pure white, here and there washed with grey. Between the eyes a white stripe; over the eyes in grey specimens a rusty-brown spot. Base of the hairs slate-grey; the tips silvery. (Forsyth Major.) Skull variable; the brain-case short and high, or long and depressed; the facial region short; posterior {56}upper pre-molar less than the anterior molar. Length of intestine, 20 inches; cæcum blunt, 1¾ inches long; main arteries of fore- and hind-limbs not broken up into a rete mirabile of small parallel vessels.

DISTRIBUTION.--This beautiful little animal, sometimes called the "Rat" of Madagascar, the smallest of all the Lemurs, is known from Ambulisatra on the south-west coast of Madagascar, and from Fort Dauphin on the south-east coast.

II. THE DORMOUSE DWARF-LEMUR. MICROCEBUS MYOXINUS.

Microcebus myoxinus, Peters, Reis, Mossamb. Zool., i., Säugeth., pp. 14-20, Taf. iii. and iv. (1852); Forsyth Major, Nov. Zool., vol. i., p. 11 (1894).