89° 
‘IV. TOXODONTIA. 
FAMILIES. 
I. Teeth 44 (M 3, PM 4, C }, 1 $X2); molars of upper jaw mostly (PM 3-4, 
M 1) oblong, moderately narrowed backwards, with two folds (the ante- 
rior of which is divided) re-entering from the inner side. Incisors three 
on each side, with simple fangs; the first largest, compressed, widely 
separated from its homologue; the second smaller, trihedral; the third 
lateral and behind the second, and rudimentary: molars of lower jaw 
comparatively broad and complex: canines moderate; incisors implanted 
in a curved row. 
NESODONTIDAE. 
Il. Teeth 36 (M 3, PM 4, C 9, I 22); molars with enamel coat interrupted 
at the anterior and posterior margins ; those of upper jaw mostly (PM 3, 4, 
M 1-3) obliquely triangular, rapidly narrowed backwards, with a single 
simple fold re-entering obliquely forwards from the inner side. Incisors 
of upper jaw two ou each side, but with incisorial crowns, the outer with 
roots of nearly uniform diameter throughout, and describing the segment 
of a circle, (like those of rodents,) and with persistent pulp—(Owen): 
molars of lower jaw narrowed, especially the posterior portions ; canines 
rudimentary ; incisors in a nearly straight line. 
TOXODONTIDAE, 
LY. NESODONTIDAE. 
Extinct. 
Nesodon Owen. 
LVI. TOXODONTIDAE. 
Extinct. 
Toxodon Owen 
V. HYRACOIDEA. 
FAMILY, 
LVII, HYRACIDAE. 
Genera. 
Hyrazx Linn. 
Hyrax Gray. Euhyrax Gray. 
Dendrohyrax Gray. 
IV. PROBOSCIDEA. 
FAMILIES. 
I. Incisors of upper jaw (1+1) everted, enormously developed and modified 
as cylindro-conic tusks, with roots extending backwards and converging, 
(LV.) 
(LVI.) 
