RHINOCEROS LEPTORHINUS. 379 



specimens of Rhinoceros leptorhinus from Clacton, I have 

 compared it with the corresponding part of the femur of 

 a Rhinoceros tichorhinus, obtained from the drift near 

 Moscow. 



The first and most obvious distinction of the Clacton 

 femur is the narrower, shallower, and more oblique sur- 

 face of the shaft, immediately above the articular surface 

 for the patella ; the convex ridge continued upwards from 

 the internal and more prominent boundary of that surface 

 is broader, more rounded, and more gradually blended 

 with the shaft of the femur ; the whole surface exterior 

 to this ridge slopes more suddenly to the outer side of 

 the bone, and there is a much deeper excavation below 

 the rotular articulation. In the femur of the tichorhine 

 Rhinoceros, the transverse exceeds the antero-posterior 

 diameter of the shaft six inches from the lower end ; in 

 that of the leptorhine species, these proportions are re- 

 versed at the same part of the shaft. The outer side of 

 the femur behind the outer ridge is more concave in the 

 Clacton specimen, which measures, from the fore to the 

 back part of the external condyle, eight inches ; it most 

 probably belongs to the leptorhine species. 



In Mr. Brown's collection there are specimens of upper 

 molar teeth of the Rhinoceros leptorhinus from the till at 

 Walton in Essex. One of these is the last molar, which 

 had just come into use when the animal perished. An- 

 other specimen is a third upper molar, worn down to its 

 base. The same Geologist also possesses the germ of the 

 ante-penultimate molar of a Rhinoceros leptorhinus from 

 Grays, in Essex, in which many smaller processes are 

 sent off into the principal valley (&), in addition to the 

 larger promontory. A similar modification of a superior 

 molar tooth of the leptorhine Rhinoceros from Tuscany 



