34 ALLEN’S NATURALIST’S LIBRARY. 
with close and woolly fur. Head short and round, Eyes 
large, set close together, and having a gentle expression ; face 
short and flat; muzzle less projecting than in Loris ; ears 
small, rounded, hairy, and nearly buried in the fur; neck short; 
tail invisible externally. Limbs short; index-finger small, con- 
taining three bones ; toes remaining spontaneously contracted 
after death. Top of skull with prominent crests, globular 
behind ; facial bones conspicuously projecting in front ; 
orbits large, their inner margins separated from each other 
by a narrow flat space. Pre-maxillee not produced far in 
front; hind border of bony palate not extending backwards 
beyond the median molar. Of the upper teeth, the inner incisor 
larger than the outer, one often absent on each side; canine 
vertically very long, with a gap between it and the anterior 
pre-molar ; anterior pre-molar elongate, the posterior differing 
considerably from the anterior molar, and having a short 
cusped heel behind; posterior molar with a three-cusped 
crown. Teeth of lower jaw agreeing with those in the diag- 
nosis of the family (supra, p. 24). Vertebree in dorsal and 
lumbar regions together 23 or 24. The long flexor muscle of 
the thumb, so characteristic of the Anthropoid Apes, is present 
in Vycticebus. The interlacement of the tendons of the muscles 
of its foot (according to Huxley and Murie) closely resembles 
the arrangement in the higher Primates. The long flexor muscle 
of the toes (flexor longus digitorum) is very large, and has one 
important origin on the lower end (internal condyle) of the 
thigh-bone correlated with the powerful grasp of its hind-limbs. 
The female bears one young at a birth. 
Above, ashy-grey, rather paler below; more or less silvery 
on the back, often rufescent on the rump, with the hairs dark 
ashy at the roots; dorsal stripe from crown to loins chestnut 
