KHINOCEROS HEMIT(ECHUS. 313 



in the ' British Fossil Mammalia.' I have arrived at the 

 conclusion that it is essentially distinct from the original 

 Rhinoc. leptorhinus of Cnvier, which latter, however, I be- 

 lieve occurs in England, in beds, in some respects different 

 from those in which Rhinoc. hemitoechus prevails, and to a 

 certain extent, with different associates. In this view, the 

 exact identification of the two species becomes in its geolo- 

 gical bearings a question of much higher importance than 

 the mere rectification of a specific name. Before entering 

 on the descriptive details, it will be necessary to revert to the 

 -origin of the name Rhinoc. leptorhinus, and to trace the suc- 

 cessive opinions which have been entertained by palaeontolo- 

 gists regarding it up to the present time ; for there is not, 

 within the whole range of Mammalian Palaeontology, an ex- 

 tinct species regarding which more has been written and 

 more opposed views advanced. 



The great French anatomist, having conclusively demon- 

 strated the distinctness of the Siberian Rhinoceros from all 

 the species then known, framed his diagnostic character upon 

 the most obvious of its peculiarities, namely, the ossified 

 nasal septum, and designated it ' le Rhinoceros a narines cloi- 

 sonees,' or Rhinoceros tichorhinus. His attention was natu- 

 rally awakened to the probability of other species occurring 

 in the fossil state, in which the nasal septum would be found 

 to agree with existing species, in presenting the ordinary 

 condition of an unossified cartilage. Cortesi had discovered in 

 1805, upon Monte Zago, near Piacenza, the entire skull, in 

 fine preservation, of a fossil Rhinoceros, which he referred 

 with doubt to a young Rhin. bicomis. 1 A drawing of this 

 cranium, by M. Adolphe Brongniart, and thus carrying high 

 authority with it of a competent execution, was many years 

 afterwards forwarded to Cuvier from Milan. The figure 

 represented a cranium differing essentially in form and pro- 

 portions from that of the Siberian Rhinoceros, and most ob- 

 viously in the absence of the bony partition of the nostrils, 

 characteristic of the latter. Cuvier inferred that the Italian 

 form constituted a different species, which, in contradistinc- 

 tion, he named ' le Rhinoceros a narines non-cloisonees,' or 

 Rhinoceros leptorhinus. The specific distinctions which he 

 indicated for the latter were, that the cerebral part of the 

 skull was proportionally shorter than in the Siberian form, 

 and less projected backwards over the occiput ; the position 

 of the orbit above the fifth molar; the termination of the 

 nasal bone by a free point having no connection with the 

 intermaxillaries through a bony partition ; and the abbrevia- 



1 Saggi Geologici, p. 72, tab. vii. 



