26 ALLEN’S NATURALIST’S LIBRARY. 
THE POTTOS. GENUS PERODICTICUS. 
feromcicus, Bennett, P. Z. §., 1839, p. 100; Huxley, P..e- 
Foo4, 9.235. 
Avctocebus, Gray, P. Z.5., 1863, p. 150 ; Mivart, P.Z.5., 7864; 
p. 644. 
This genus contains two species, both confined to the 
West Coast of Africa. ‘The Pottos are slender-bodied ani- 
mals, with oval heads and blunt Dog-shaped muzzles. ‘Their 
eyes are large and full, and their external ears erect, with 
shelf-like lamelle inside. They have slender and sub-equal 
limbs. The second digit of the fore-limb is rudimentary and 
nail-less; it is supported on one wrist-bone, and has two 
phalanges or finger-bones. The great toe is opposable, and 
the fourth and fifth digits of both limbs are united together 
by membrane as far as the first joint. The processes of the 
vertebre in the neck and back are long and protruding. ‘The 
tail is very short. 
The pre-maxillz (which carry the incisor teeth) do not project 
in front, nor does the bony palate extend farther back than the 
end of the posterior molar teeth. Of the upper teeth the 
incisors are equal in size (Fig. 6); the median and posterior 
pre-molars have on their crowns three cusps, of which the two 
outer are the larger ; the anterior and median molars are cin- 
gulate, have four-cusped crowns, and are larger than the pre- 
molars ; the posterior is narrow from before backwards, and its 
crown presents only two or three cusps. Of the lower teeth, the 
anterior pre-molar is recurved and larger than the canine, witha 
ridge on its inner face and a cusped heel behind ; the median 
and posterior ones are shorter than their anterior fellow, each 
having a strong posterior cusped heel; the anterior and median 
