330 RHINOCEROS. 



adult dentition of the two-horned Rhinoceros of the Cape. 

 For the other existing species, the beautiful figures given 

 by De Blainville in the ' Osteographie ' may be referred to 

 generally in illustration of the same character. In Rhin. 

 tichorhinus the crochet is given off at a very open angle, and 

 is united with the ' combmg plate ' of the outer ridge, so as to 

 form the third fossette ; the same occurs in the molars of 

 Rhin. simus, which in their general plan bear a close affinity 

 to those of Rhin. tichorhinus. In regard to the other fossil 

 species, there are but few specimens figured in the ' Ossemens 

 Fossiles ' that can be referred to in illustration. The molar 

 from Chagny (Departement du Saone et Loire), PI. VI. fig. 6, 

 cited by Kaup, as an illustration of his Rhin. Merckii, is far 

 advanced in wear, but what remains of the ' crochet ' exhibits 

 the same very open angle in its offset from the posterior 

 barrel. Of the two molars from Crozes (Depart, du Gard), 

 also cited by Kaup as of Rhin. Merckii, and adduced by Pro- 

 fessor Owen as identical with his Rhin. leptorhinus of Clacton, 

 the specimen fig. 5 of PI. XIII. is ground down so low 

 that the crochet has nearly disappeared, and it is therefore 

 hardly a suitable case for comparison ; but if it is compared 

 with m. 2 of fig. 2, PI. XVI. of the accompanying illus- 

 trations, being a penultimate of Rhin. hemitoechus which is 

 nearly in a corresponding state of abrasion, it is manifest 

 that in the former the curve of the crochet forms a much 

 less abrupt flexure than in the latter. The second Crozes 

 specimen (Oss. Fossiles, Rhin., PI. XILI. fig. 4) is an abnormal 

 case, the nature of which has been clearly explained by 

 De Christol, in which the crochet is so produced as to be 

 concrete with the middle of the anterior colline, thus leading 

 to the early isolation of a third fossette, in a manner different 

 from what occurs, as an ordinary condition, either in the true 

 molars of Rhin. tichorhinus or in any other known species. 

 But although so little worn, that the posterior valley is not 

 yet isolated into a fossette, if the figure given by Cuvier 

 is compared with fig. 3 of PI. XVI. of the accompanying 

 illustrations, it will be seen that the anterior edge of the 

 posterior colline does not form an acute angle and a re- 

 entering niche with the base of the crochet. 



Of the European fossil forms from the Pliocene and more 

 recent deposits, Rhin. megarhinus is that of which the den- 

 tition is best known, after Rhin. tichorhinus. The excellent 

 descriptions and figures supplied first by De Christol, and 

 afterwards by Gervais, leave little to be desired in regard to 

 the cranial and dental characters of this species. In fig. 5, 

 PL III. of his memoir (reproduced in PI. XVIII. fig. 3), 

 De Christol has given a fine illustration of the natural size 



