74 
b. Body somewhat leporiform, with the hind limbs much longer than 
the fore, (as in the Leporids.) Teeth comparatively differentiated. 
DICHOBUNIDAE. (XXXIX.) 
II. Molars (M) attypically tuberculiferous. Canines of lower jaw enlarged 
and often developed as tusks, entirely differentiated and distant from 
incisors. Palatine bones scarcely contracted behind, thick, and (at the 
walls of the posterior nares) articulated with the terminal portion of the 
supramaxillary bones. Digestive system not adapted for rumination: 
stomach imperfectly septate.—Axis with the odontoid process conical. 
(Flower. )—( Omnivora.) 
A. Body massive, with the feet phalangigrade, and their external (2, 5) 
. toes well developed and produced as far as or beyond the first phalanges 
of the middle (3—4) toes; the last phalanges wide and with convex 
Margins: manus with unciform bone much broader than high, and with 
second phalanx wedged between trapezoid and magnum; pes with 
cuboid broader than high. Lower jaw with a deep preangular expansion 
directed forwards. (Snout rounded and with the nostrils open upwards 
and sideways. Mammae two, inguinal.) Obesa. 
-o 
Molars of upper jaw witha bow-shaped (convex extrorsely) longitudinal 
and a straight transverse valley dividing four tubercles, all of which are 
convex introrsely (towards the palate) and concave externally, (thus 
simulating the teeth of ruminants.) Molars of lower jaw narrower than 
those of upper, and with the longitudinal valley very narrow: (last 
molar with a supplementary posterior lobe.) Canines comparatively 
small and cylindro-conic. ( Merycopotamoidea. ) 
MERYCOPOTAMIDAE. (XL.) 
! Molars (M) of upper jaw with nearly straight or irregularly sinuous 
longitudinal and transverse valleys dividing four tubercles, of which 
the external two are convex extrorsely and the inner two convex in- 
trorsely (towards the palate.) Molars of lower jaw resembling those 
of upper, (the last molar with a supplementary posterior lobe.) 
Canines very large and furrowed along their posterior surface. (Hip- 
popotumoidea.) 
HIPPOPOTAMIDAE. (XLI) 
B. Body suiform; with the feet unguligrade, and their external toes re- 
‘duced in size and not produced or assisting in progression; the last 
phalanges elongated and trihedral: manus with the unciform little or 
no broader than deep, and with the second phalanx not wedged be- 
tween the trapezoid and magnum; pes with cuboid deeper than broad 
and emarginated behind. Lower jaw with no preangular expansion. 
(Snout disciform and with the nostrils in it and open forwards. Mam- 
mae in increased number (4 to 10), ventral as well as inguinal.)  Seti- 
Sera. 
1. True molars of upper jaw with oblong crowns with four or more 
principal sub-conical lobes and accessory smaller ones. 
