_Microcebus coquereli_, Mivart, P. Z. S., 1867, pp. 966-967; Forsyth Major, Nov. Zool., vol. i., p. 14 (1894; with full synonymy). _Mirza coquerelii_, J. E. Gray, Cat. Monkeys, Brit. Mus. App., pp. 131, 135, 136 (1870); Schlegel, Mus. Pays Bas, vii., p. 321 (1876). CHARACTERS.--Similar to _M. furcifer_, but slightly smaller; ears large, long, and almost naked; tail longer than the body; fur soft and woolly. Above dark grey, washed with rufous; tail, at base, of the same colour as the back; remainder of tail dark rufous; throat, breast, and under side of body yellowish-grey. {61}Length of body, 8½ inches; tail, 13 inches; skull high and arched; outer and hinder portion of ear-capsules (periotic-bones) and squamosal swollen; frontal bone longer than in _Opolemur_ and _Chirogale_; occiput less sloping from behind and above forwards and outwards. Upper median and posterior molars with one inner and two outer cusps, united by a curved ridge, cingulate all round, and with a small cusp or cingulum at the hind inner angle; posterior pre-molars smaller and shorter than the molars, with strong and vertically longer outer cusp, and a much more feeble inner cusp; posterior lower molar lengthened behind by a fifth cusp. DISTRIBUTION.--Coquerel's Dwarf-Lemur, or the "Sisiba," as the natives call it, is found round Passandava Bay, near Mouroundava, on the south-west coast of Madagascar. HABITS.--The Sisiba, like its congeners, is nocturnal and arboreal, constructing in the trees a nest of twigs. It feeds on fruits and leaves. THE FAT-TAILED LEMURS. GENUS OPOLEMUR. _Opolemur_, J. E. Gray, P. Z. S., 1872, p. 853. The term _Opolemur_, by which this genus is designated, is not altogether appropriate, and is, indeed, even somewhat misleading. It was applied in the first instance to the typical species on account of the thickened base of its tail, which in the type-specimen was a very conspicuous character. The deposit of fat by which this thickening was caused was not then known to be merely transitory--a store of food collected at the base of the tail and on other parts of the body, to supply the needs of the animal during the arid and foodless season, when it retires into a state of torpidity. It is now known that {62}other species of this sub-family (as we have seen above in the case of the Mouse-Lemurs), which are generically distinct from _Opolemur_, share this peculiarity.