SIWALIK AND NARBADA BUNODONT SUINA. 
65—99 
talon of m. 3 ; although the absence of the first premolar is a more specialized 
character, albeit one found in some tertiary species (S. eri/manthius, etc.). The stout 
premolars and the short m. 3 of some of the tertiary forms like S. palceochoerus and 
jS. hijsiidriciis indicate that it is not improbable that the river-hogs may have 
descended from some such form. B. harhatus in its small m. 3 almost certainly shows 
signs of a direct descent from a primitive stock ; and the writer is inclined to think 
that the same may be said of 8. vittatus and the 8. andamanensis group. The 
resemblance of the teeth of the latter to those of 8. hysudricus renders it by no 
means improbable that the one may be the descendant of the other ; and if the 
writer is at all correct in su]3posing that 8, vittatus is descended from 8. giganteus this 
would indicate that the 8. vittatus and the 8. andamanensis groups are not specifically the 
same. The first and second molars of 8. vittatus are relatively longer than in 8. 
giganteus^ which is a character that might be expected to occur in the newer form. 
The longer m. 3 of 8. cristatm indicates that it may well be a more specialized form 
of the 8. vittatus stock. The proportions of the molar teeth of 8. verrucosus are not 
unlike those of the form here named 8. titan (assuming that to be distinct from 8. 
giganteus), with the exception that ni. 3 is generally longer in proportion to the two 
preceding teeth^ ; and the writer would suggest the possibility of the one being the 
degenerate descendant of the other. In any case it is highly probable that the 8. 
verrucosus, 8. vittatus (including 8. cristatus), and 8. andamanensis groups are 
descendants of some of the three medium or large forms of Siwalik pigs with simple 
molars ; and the undoubted existence of the three fossil forms^ renders it, primd facie, 
probable that the existing Asiatic species (exclusive of 8. harhatus and 8. salvanius) 
are more than two in number. The probability of the descent of 8. salvanius from 
8. punjahiensis has been already noticed. 
Bahirussa in its simple molars shows evidence of affinity with some of the 
primitive forms ; and the same may be said still more decidedly with respect to 
Dicotyles. The connection of the latter genus with FT ijotherium and its allies cannot 
be determined till the affinities of the extinct America genera noticed above have 
been fully worked out. 
1 
Family III. : ENTELODONTIDBE.^ 
Genus: TETRACONODON, Falc. 
Species : Tetraconodon magnus,^ Falc. 
This genus and species, which are both peculiar to the Siwaliks are only known 
The dimensions of the upper molars of three specimens of S. verrucosus are as follows : — 
m. 1 m. 2 
1. Borneo . 1'24 
2. Java 1-53 
3. Ceram ......... 1'54 
m. 3 
1'24 
1-49 
1-47 
2 Even if S. Man should he eventually proved to he only a large variety of 8. giganteus, the lower j aw provisionally 
assigned to the latter will indicate another species. 
3 Prof. Elower (“ Catalogue of Osteological Specimens in Mus. Roy. Coll. Surgeons,” pt. II., p. 341, 1884) refers the 
present group to the family Chmopotamidce. He also adopts the generic term Motherium, Pom. (1847), in place of Entelodon, 
Aym. (1848) ; the very general acceptation of the latter by continental palaeontologists induces the present writer to retain it. 
ArchcBotherium, Leidy, is a later synonym. 4 Olim, magnum, errorim. 
