RHINOCEROS LEPTORHINUS, 357 
Cuvier to the species in question, were suggested by the 
characters of the fossil skull of a Rhinoceros discovered by 
M. Cortesi in a fresh-water upper tertiary deposit at Plai- 
sance, as they appeared in a drawing transmitted to Cuvier, 
who had not had an opportunity of studying the original, 
which is preserved in the ‘ Musée des Mines’ at Milan. 
Confiding in the drawing, which is engraved in the ‘ Osse- 
mens Fossiles,’ 4to., 1822, tom. ii., pt. 1., Rhinoceros, pl. 
ix., fig. 7, Cuvier was led to conclude that the Rhino- 
ceros of Plaisance differed from that of Siberia and north- 
ern Hurope in having ‘the cerebral part of the skull less 
prolonged and less inclined backwards; in the position 
of the orbit above the fifth molar tooth; in the anterior 
termination of the nasal bones by a free point, and in 
the absence of any attachment of them to the intermaxil- 
laries by a vertical osseous septum; in the minor degree 
of prolongation of the intermaxillary bones, which were 
of a totally different form, presenting, in short, as 
little as the nasal partition, any of those characters for 
which the skull of the Lhinoceros tichorhinus was so re- 
markable.” (Tom. cit. p. 71.) From these apparently 
broad distinctions, Cuvier did not hesitate to admit the 
specific difference of M. Cortesi’s Rhinoceros ; and he even 
ventured to state that it incontestably approached nearer 
to the Rhinoceros bicornis of the Cape than to any other 
known species. (Tom. cit. p. 71.) 
This summary of the cranial characters of the Rhinoceros 
leptorhinus is repeated without modification in the post- 
humous 8vo. edition of the ‘Ossemens Fossiles,’? 1834, 
tom. 11, p> la: 
In the following year, however, M. de Christol commu- 
nicated to the ‘ Annales des Sciences,’ 2° série, tom. iv., p. 
44, a more accurate figure (pl. ui, fig. 4) of the cranium 
