54 LLOYDS NATURAL HISTORY. 



THE DWARF-LEMURS. GENUS MICROCEBUS. 



Mtcrocebus, Geoffr., Cours de I'Hist. Nat., Mamm., legon 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 Gala- 

 gos. Their snout is also shorter ; their eyes are large, approxi- 

 mated together, very prominent and very bright, and their ears 

 are elongated. On the ventral surface are situated four mammae, 

 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 in- 

 cisor 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 {citiguluni) 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 down- 

 wards. 



