SIWALIK AND NANBADA BUNODONT SUINA. 
7-41 
Depth of ramus at m. 2 
Length of five last check-tccth 
,, ,, m. 1 
Width ,, ,, ,, 
Leng-tli ,, ,, 2 
Width „ ,, ,, 
Length ,, ,, 3 
Width „ ,, ,, . . 
Specimen. 
Typical form.l 
4-2 
4-4 
7-7 
8-5 
1-21 
Lo 
0'95 
1-3 
1-68 
1-9 
1-22 
1’55 
2-2 
2-82 
1-3 
1-6 
These dimensions show that while the depth of the ramus is practically the 
same in the two specimens, there is a great difference in the absolute size of the 
teeth : the hinder border of the symphysis is also placed farther forward in the 
smaller jaw, and the true molars are proportionately slightly narrower. In the first 
notice of this specimen^ it was thought that it might belong to 11. iravaticiis^ but an 
examination of the original specimens on which that species was founded has 
shown that the present specimen is too large, and has too short a symphysis to 
belong to that form. It is not, however, improbable that it should be referred to the 
form which is here proAusionally termed H. sivalensis, var. angiistidens. 
VertehrcB and limb-hones. — An extensive series of these bones are contained in the 
British and Indian Museums, but have never been compared with those of other 
species, although a large number from the former collection are figured in the 
“ F.A.S.”'* The following points in which some of the Siwalik bones differ from 
those of II. amphibius may be recorded : — The spinous process of the axis is higher 
vertically and shorter antero-posteriorly, and the odontoid process blunter and 
directed more upwardly. The scapula has its long diameter shorter, and its fore- 
and-aft borders more curved. Of the femur there are two forms, in one of which 
the head is very similar to that of II. amphibius, while in the other it is more 
prominent, and approaches that of the same bone in one of the Narbada species : in 
the former the trochlear surface for the patella is less deeply excavated, and its 
superior border less sinuous than in II. amphibius, thus indicating a lesser degree of 
specialization : the shaft is apparently stouter. These differences confirm the 
suggestion that II. sivalensis may really include more than one species. The 
astragalus (of which also there seems to be more than one form) is decidedly longer 
than the corresponding bone of H. amphibius, wadi thereby makes a marked step in 
the direction of the pigs. 
A ffinities. — The long mandibular symphysis, the three pairs of incisors in each 
jaw, the small prominence of the orbits, and the elongated astragalus, are all 
characters clearly indicating that this species is of a less specialized type than the 
living members of the genus. 
Distribution. — This species occurs in the typical Siwalik Hills, where its remains 
are extremely common, and continues into the w^estern Punjab, where it is equally 
rare. It is unknown from Sind and Perim Island. Remains of the genus occur in 
Burma, but have all been referred to the next species. 
1 Taken from a specimen in the Indian Museum. 2 ‘ Eecords,’ vol. XV., p. 32. 
3 Vide inf ra. 4 ITates LXIll., efi »ej. 
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