133 Uoyal Socicii/. 



It has not yet been proved to have existed in Europe anterior to the 

 deposit of the Boulder Clay. The second species, the B. megarhinus 

 of M. de Christol, characterized by its slender limbs and the absence 

 of the " cloison," has been determined by the author among re- 

 mains from the brick-earths occupying the lower part of the 

 Thames valley, and from the Preglacial forest-bed of Cromer. The 

 species ranged from the Norfolk shore southwards through Central 

 France into Italy. In France and Italy it characterizes the Pliocene 

 deposits, being found in the former country in association with 

 Mastodon brevirostris and Halitherium Serresii, in the latter with 

 M. Arvernensis. From its southern range we may infer that the 

 megarhine species was fitted to inhabit the warm and temperate 

 zones of Europe, just as the tichorhine was peculiarly fitted for the 

 endurance of an Arctic winter. 



The third species is the R. etniscus of Dr. Falconer, confined to 

 the forest-bed of the Norfolk shore, and, like the JR. megarhinus, 

 found in the Pliocenes of France and Italy ; it ranged across the 

 Pyrenees as far as Malaga, and is the only species known to occur in 

 Spain. 



The fourth, the R. leptorhinus of Professor Owen, is the equivalent 

 of the R. hemitcechus of Dr. Falconer. It is defined as " R. a narines 

 demicloisonnees," and is probably not the same animal as the R. 

 leptorhinus or " R. a narines non-cloisonnees" of Baron Cuvier, the 

 evidence as to the absence or presence of the cloison in the type of 

 the species being of the most conflicting nature. In Central France 

 it is identical with R. mesotropus and R. velaunus of M. Aymard, 

 the R. Aymardi of M. Pomel, and the R. leptorhimis (du Puy) of 

 M. Gervais. Its dentition is characterized by the presence of the 

 third costa in the upper molar series, coupled with the stoutness 

 of the cingulura, the suppression of the anterior combing plate, the 

 smoothness of the enamel, and the extent to which the upper molars 

 overhang the lower, which causes the enamel on the outer side of 

 the latter to be worn obliquely. The lower molars can be deter- 

 mined by the flattening of the anterior area, coupled with the fine 

 sculpturing of the enamel- surface. In common with the other 

 fossil British Rhinoceroses, it possessed a molar series of six only on 

 either side, and was bicorn. It ranged through England, from the 

 Hysena-den of Kirkdale in Yorkshire in the north, as far south as 

 the plains of Somersetshire, and as far to the West as Pembroke- 

 shire. It is very generally found in association with Elephas anti- 

 quus and Hippopotamus major, both species which lived in Pliocene 

 times. The association in Wookey Hole Hysena-den with Elephas 

 primigenius and R. tichorhinus and other characteristic Postglacial 

 mammals proves that it coexisted with the tichorhine species, to 

 which it probably bore the same geographical relation as the Elk 

 does to the Reindeer in the high northern latitudes. The sum of 

 the evidence proves that it was coeval with the Mammoth and 

 tichorhine Rhinoceros, and does not characterize deposits of an 

 earlier epoch in the Pleistocene. It has not as yet been found in 

 Preglacial formations. The R. leptorhinus is more closely allied to 

 the bicorn Rhinoceros of Sumatra than to any other living species. 



