Chapter 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.