]04 
TEliTJAllY YEETEBliATA OF THE FATCM. 
Ilio ])oini of tlie T]])])or canine tusk, while in IJlotheiium, a more nearly related form, 
tli('re ar(> sometimes two ])airs of such processes, but they are directed downwards and 
mor(' or less club-shaped: iu the latter genus also their function is uidviiown. 
On the side of the jaw' there are several foramina. The most anterior of these is 
immediately behind the alveolus of i. 1, the next tw'o are beneath i.3 and c., while the 
last is behind the posterior border of the symphysis at the level of 2. 
The first ineisors (i. 1) are broken ofl' short, but it can be seen that they were greatly 
enlarged and directed forwards. They were laterally compressed so as to give an 
elongated oval outline in section ; the outer side, at least, was enamel-covered. The 
second incisor (?'. 2) was a small rounded tooth, represented in this specimen by its 
alveolus only. Behind this, at an interval of about cm., is a small rounded root of 
a tooth and immediately behind this a second rather larger. The nature of these is 
doubtful : they look as if they might be roots of one tooth, but since from their position 
this is not probable, they are here regarded as the roots of the third incisor (h 3) and 
the canine (r.). The distance betw'cen the canine and first premolar is about 1 cm. This 
enlargement of the anterior incisors and the very small size of the canine distinguish 
Geniohi/us from the other members of the family, and at least justify its separation in a 
distinct subfamily. The anterior premolar 1) is a compressed tooth consisting of small 
anterior and posterior tubercles and a high main cusp. In the next (/7m. 2) there is a small 
cingular ridge in front of the tooth and the main cusp is much larger, showing a tendency 
towards division into an outer and an inner element. In wear it gives a triangular 
surface, from the outer angle of which a ridge runs down the outer face of the tooth, 
w'hile from its front angle there is a small ridge connecting it with the anterior tubercle, 
and similarly posteriorly a small ridge unites it with the posterior tubercle. The next 
tooth (pin. 3) is similar, except that the [)osterior lobe is larger and shows a tendency to 
give a V-shaped surface in wear. In the last premolar {jiin. 4) the replacement of the 
main cusp by two elements is complete, the inner being small and rounded, the outer 
larger and V-shaped in wear. From the anterior arm of the V a small ridge runs to the 
small anterior tubercle, while from the posterior a low ridge runs back uniting it with 
the anterior limb of the V-shaped posterior lobe. On the inner side of this last there is 
a trace of a small inner tubercle corresponding to the postero-internal cusp of the molars. 
The characters of the molars are those of a ])rimitive mend)er of the Suidos, in which 
the outer cus})S are distinctly selenodont. Each molar consists of two pairs of cusps, the 
outer V-shajied, the inner more rounded or ])yramidal. In the tirst molar (m. 1) the 
out(‘r cusp is considerably w'orn ; it consists of the main tubercle forming the apex of 
the V, of which the arms form slight ridges terminating in small accessory tubercles, of 
which the anterior is situated on the anterior border of tbe tooth, while the posterior is 
connected by a slight ridge with the postero-internal angle of the inner cusp. The 
jiostero-external cusp shows the selenodont character still more clearly: its small anterior 
accessory tubercle partially fills the main transverse valley ; the posterior accessory 
tubercle is on the hinder border of the tootlu. The internal cusps are trihedral, and 
in wear they also show some tendenc:y to form a V-shaped surface, the opening of the 
V of the antero-internal cusp looking outwards and backwards, that of the postero- 
internal cusp outwards and forwards. There is a slightly developed cingulum on the 
outer siile of the tooth, most marked opposite the opening of the transverse valley and 
