SIWALIK SELENGDONT SUINA, ETC. 
31—172 
well-defined ‘ cingulum ’ on tlie internal surface of the one complete inner column 
which now remains. The length of the specimen is 058 inch, and the height of its 
outer column O’ 34 inch. 
Comparisons . — There can be no question as to the generic distinctness of the 
tooth under consideration from the molars of the other Siwalik selenodont pig-like 
animals ; neither can it be identified with those of any European representative of 
the same group. Turning, however, to the American Oreodontidce, the tooth will be 
found to resemble very closely in general structure the molars of the genera Oreodon, 1 
Eporeodon, Agriochoerus, and Merycochcerus? A comparison of- the specimen with the 
admirable figures of the molars of these genera given by the transatlantic 
palaeontologists, as well as with actual specimens and casts in the British Museum, 
has shown that the resemblance is so close that there seems no doubt but that the 
Indian specimen should fie referred to some member of the same family. The 
molars of Oreodon ( Eporeodon ) major seem, except in the matter of size, to come very 
close to the Indian tooth : the form of the ‘ cingulum ’ and inner columns being 
strikingly similar in both. In the matter of size, the Indian specimen comes nearer 
to the molars of 0 . culbertsoni , 3 but in those teeth the valleys are less completely open*_ 
The nearest approach to the Indian tooth seems, however, to be made by the teeth of 
Agriochoerus latifrons. If the figure given in this memoir be compared with the very 
excellent woodcut of an upper molar of the latter species, given (after Professor 
Leidy) by Professor Gaudry, on page 98 of the oft-quoted “ Enchainements du 
Monde Animal,” it will be seen that (as far as the imperfect condition of the Indian 
tooth will permit of comparison,) there is an almost, if not complete, identity 
between the two specimens, and they might very readily be taken for the teeth of 
the same species. The absence of the external surface of the Indian tooth renders it 
uncertain whether the form of this part would be precisely the same as the American 
tooth, and as there appears to be some difficulty in always distinguishing isolated 
teeth of Agriochoerus , Oreodon and Mcrgcochcerus, it would not be safe to identify the 
Indian tooth with A. latifrons , though it would be unwise to say that it might not 
belong to that species. It seems, however, certain, as already said, that the tooth 
belongs to the Oreodontidce , and it is accordingly provisionally referred to the genus 
Agriochoerus , with the possibility of its belonging to the American species A. latifrons. 
With this possibility in view no specific name is assigned to the Indian tooth, and it 
must also be borne in mind that there is a further possibility that the generic 
determination may eventually be proved incorrect, though this is improbable. 
1 Leidy loe. cit., pi. VII., fig. 7 to 12. 
2 Ibid, figs. 1 to 6. 
Ibid, fig. 12. 
