74 
Records of the Geological Survey of India. [vol. xi, 
aiul relative size. The dimensions of tlio first upper true molar of 8. diftii 
rei.resented in figure 2 of Plate XXX of tlie P. A. S. are as follows: 
Length g'l 
Width 3'3 
Interval between 3rd and 4th ridges . , , .1*2 
The new tooth is, therefore, relatively narrower, and is further distinguished 
by having a lai'ge hind talon which is wanting in 8. diflii. Of Falconer’s species 
of 8tegodon there therefore only remains S. limMfrons to which our specimens can 
belong; as the third molar of this species has six ridges, the first true molar 
should also have six ridges, and at fii’st I thought of referring the teeth under 
discussion to 8. honibifrons had it not been for certain reasons to be immediately 
noticed. 
The true molar in this jaw agrees with the second milk-molar of a 8tpgodon 
from China, referred by Professor Owen' to a new species under the name of 
8. sinensis, in the following characters; both these teeth have cuiwod transverse 
ridges, which carry from fourteen to fifteen tubercles, and have a slight median 
division of the ridges. In both teeth there is an imperfect ridge at the anterior 
end, which joins the middle of the first complete ridge: this imperfect ridge I 
consider to be only a talon, though Professor Owen regards it as the first true 
ridge. From a comparison of the Chinese and Siwalik specimens, I have not the 
.sliglitost doubt but that they belong to the same species; the length of the 
Chinese second milk-molar is 2-9 inches and its width 2'0 inches: dimensions 
which would well correspond to those of the tooth which should precede the third 
milk-molar in the Siwalik specimen. 
We have now to consider another first upper molar of a 8terjn(Ion from the 
Pun jab which I will designate as h ; this tooth can’ies only six ridges, and cannot 
tliex'efore belong to 8, instxjnis or 8. gimesii. These ridges are very closely 
approximated and run straight across the tooth ; there is a large hind talon. The 
length of this tooth is t'O inches, its width 2'9 inches, and the distance between 
the third and fourth ridges 0’8 inch. From those dimensions it will be quite 
api)arent that this tooth is not the first true molar of 8. diftii, nor of the Chinese 
species. It at one time occuiTcd to mo that this tooth might bo the third milk- 
molar of 8. diftii, but the approximation of the ridges is against that view. 
Again, the length of the worn third milk-molar of that species represented in 
figure I of Plate XXX of the F. A. S. is only 3'3 inches and its width 2 inches; it 
is therefore clear that tooth h does not belong to 8. diftii. 
Now, with regard to 8. hombifrons, tooth h agrees with the hinder molars of 
that species, in having broad and blunt ridges, (“ Palaeontological Memoirs,” Vol. I, 
p. HI,) in having a hind talon, and having fewer ridges than the first molar of 
8. insignis. There is, therefore, every presumption of this tooth being the first 
true molar of 8. hombifrons. 
This being so, the first molar a and the Chinese tooth cannot belong to 8. 
lyojwSx/roris, and since they do not belong to any other of Falconer’s Siwalik species, 
wo must retain for these Owen’s name of 8. sinensis. 
* Quar, Jouru. Geol. Soc. Loud., Vol. XXVI. p. 417, pi. 27. 
