255 
The posterior, unpaired lobe, or heel, has a more median, less internal 
position, and is very much higher than is usual in the existing species. 
In the latter the heel varies very much in development, but I have 
seen no specimen in which it is so high as in the fossil. T^urther, in 
the fossil the heel is separated from the posterior pair of cusps by a 
much more profound cleft, while the oblicjue, tuberculated ridge, con- 
necting the heel with the postero-internal cusp, is but feebly indicated, 
and much less prominent than in H. amphibins. As in the modern 
species, an external cusp is imperfectly separated from the heel, but is 
much higher and more distinct than in H. aviphibius. On the pos- 
terior face of the heel is a groove, not present in the modern species, 
which appears like an incipient additional internal cusp. The cingulum 
is distinctly indicated on the anterior and posterior faces of the crown ; 
posteriorly it is hardly so thick or prominent as in the existing 
species, but on the anterior face it is far higher than in the latter, 
rising for more than half the height of the anterior pair of cusps. 
Two isolated lower premolars, contained in the collection, so 
resemble the type -specimen in appearance, mode of preservation, 
and degree of abrasion, that they might very well have been 
derived from the same individual. If so, however, they are relatively 
somewhat smaller than in the recent species. 
The first tooth (P. 2 of the original series) is rather smaller and 
more slender than in H. amphibiiis, irom which it further differs in the 
presence of a small tubercle on the inner side of the principal cusp 
(protoconid), and in the much more prominent cingulum, which com- 
pletely encircles the crown, and is especially strong on the internal, 
anterior, and posterior faces. 
The second premolar (P. 3) differs from that of H. amphibius in 
the more prominent cingulum, in the absence of a posterior basal 
tubercle, and in the presence of a sort of buttress on each of the outer 
and inner sides of the principal cusp (protoconid), demarcated by 
shallow grooves. 
In the subjoined table the measurements of the teeth of H. am- 
phibius are taken from the unusually large individual mentioned above. 
All the measurements are in the metric system. 
Measurements. 
H. amph. H. pond. 
Third lower molar (M. 3), length (ant. -post. diam.)... '0775 "076 
„ „ ., width (transv. diam.) "0425 '0375 
„ ,, ,, height of heel "037 -048 
First lower premolar (P. 2), length '035 "032 
Second lower premolar (P. 3), length '046 "037 
The skeletal remains are not sufficiently characteristic for 
description. 
BUBALUS, Frisch. 
The Buffalo is represented by an incomplete right ramus man- 
dibuli, which retains the second and third molars and the alveoli of the 
other cheek-teeth, but lacking the symphysial region, condyle, coro- 
