106 ALLEN’S NATURALIST’S LIBRARY. 
hair forming a fringe all round. Median nose-pad high and 
narrow ; pupil of eye circular ; body elongated ; arms about 
one quarter of the length of the legs ; hands very long, the four 
outer fingers united by a membrane as faras the first joint, and 
the toes to the centre of their middle segments ; hands and feet 
haired to the tips. ‘Tail rudimentary. 
Skull longer and less vaulted ; brain-case proportionately 
more compressed from side to side; the muzzle longer, and 
the orbit smaller, than in Avahis ; floor of orbit higher than 
the bony margin of the jaw ; inter-orbital space flat ; nasal bones, 
though long, not extending in front as far as the end of the pre- 
maxillary bone ; mandible elongated, narrower, and less deep 
than in Avahis. Bony palate short, posterior margin thickened, 
and with a foramen behind the posterior molar; line of union 
of the two halves of the lower jaw shorter than in Avahis ; 
its angle very large. No central bone in the wrist (or 
carpus); hindlimb (with or without the foot), compared with 
the fore-limb (with or without the hand), longer than in any 
other of the Primates, except Galago. Upper teeth: Incisors, 
sub-equal, set close together and subject to variation in size ; 
canine, vertically taller than, and not separated by a gap from, 
the pre-molar; pre-molars compressed, ana havingan inner cusp ; 
anterior molars, four-cusped, with the supplementary cusps 
weak, and with no oblique ridge; anterior and median, with 
their outer and inner cusps opposite; posterior molar, which is 
the smallest grinder of the jaw-—four-cusped, with transverse, 
but no oblique ridges. Lozer teeth: Incisors, with marked 
longitudinal ridges to the outside (peculiar to this genus) ; pre- 
molars sub-equal; molars all four-cusped, and the posterior ones 
expanded behind. 
Brain highly organised. A large laryngeal pouch (present 
