RHINOCEROS LEPTORHINUS. 361 
appears to be the same scale as that on which Dr. Kaup’s 
specimen of the lower jaw of the Rhinoceros Merchii 1s 
figured in the ‘ Akten der Urwelt,’ tab. u1. 
The socket of the second molar, (p 2,) or the sixth, count- 
ing from behind forwards, is entirely in advance of the 
transverse line drawn across 
Fig. 133. 
the back part of the symphysis, 
and the molar series 1s conse- 
quently extended much closer 
to the end of the jaw than 
in the Rhinoceros tichorhinus. 
This part of the symphysis also 
is rounded inwards towards its 
anterior termination in the pre- 
sent specimen, producing a very 
different contour from that pro- 
duced by the swelling out of 
the same part to form the flat- 
tened spatulate extremity, cha- 
racteristic of the lower jaw of 
the Rh. tichorhinus (fig. 124). 
The lower border of the jaw is 
less curved in the Rh. leptorhi- 
nus, and the depth less sudden- 
ly diminished at the symphysis. 
The fore-part of the base of the 
coronoid process is more promi- 
nent externally in the Lh. lep- 
torhinus than in the Rh. ticho- 
rhinus. The molar teeth are 
larger, and the series occupies 
a greater extent in the jaw Lower jaw, Rhinoceros leplorhinus. 
c ‘ v ith nat. size. Clacton, Essex. 
of the leptorhine species. 
