1868.] DAWKINS KHINOCEROS ETKUSCUS. 211 



there is a fine upper true molar 1 (PI. VIII. figs. 3 «, 3 b) from the Val 

 d'Arno, which is but little worn, and therefore belonged to an ado- 

 lescent animal ; as compared with the English specimens it is re- 

 markable only for its smaller size. The guard, o, is represented on 

 its inner aspect by a line of cusps passing across the second collis, e, 

 and blocking up the entrance of the anterior valley, a. In the same 

 museum, also, there is a plaster cast of a skull containing five out of 

 ihe six teeth. The first premolar presents the same feature as that 

 described in the specimen from Etampes. The two posterior comb- 

 ing-plates have insulated a portion of the anterior valley, as in PI. 

 VIII. fig. 1 ; and there consequently appear on the worn crown-surface 

 three islands of enamel*. In the Oxford Museum there is a frag- 

 ment of the maxillary bone containing premolars 3, 4, and true 

 molars 1, 2, brought from the Val d'Arno by Mr. Joseph Pentland. 

 The teeth are very much shattered, with the exception of the first 

 true molar. They present all the characters of the Etruscan species. 

 This specimen is highly impregnated with iron, and has been derived 

 from a sandy matrix. From the same deposit are preserved the 

 teeth of Eleplias meridionalis, E. antiquus, and Hij^popotamus major ; 

 and its fluviatile or lacustrine- origin is proved by the presence of a 

 large species of Anoclon'\. Evidence also is afforded by an upper 

 jaw of the animal found at Malaga, and now preserved in the British 

 Museum, that the animal lived in the south of Spain. The teeth, 

 which consist of the whole molar series, except premolar 4, agree 

 exactly with those which have already been described J. 



4. Permanent Lower Molar Dentition. — The lower molar series 

 (PI. VII. fig. 3) oi Rhinoceros Etruscus is easily distinguished from that 

 of the Megarhine species, with which it is associated on the Cromer 

 shore, by the possession of the following characters : — The teeth are 

 much smaller and the unworn crowns are much lower. In the true 

 molars also, the guard, o, before and behind is much more strongly 

 marked. In true molars 1 and 2 it frequently crosses the base of the 

 posterior area, n, and disappears in the median groove, i, and is 

 always represented more or less by a line of tubercles. This cha- 

 racter is strongly exaggerated in the premolars, in which there is a 

 similar prolongation of the anterior guard backwards to meet the pos- 

 terior in the middle of the median groove, {. The enamel structure 

 throughout is also rougher than in the Megarhine teeth. As com- 

 pared with the Leptorhine and Tichorhine species, it is differentiated 

 by the presence of the guard, o, on the external lamina, by the low- 

 ness of the crown, the thickness of the enamel, and by the absence 

 of costoe from the rounded anterior area, m. The finest specimen 

 that has passed through my hands consists of the two rami that 

 belong to the same animal as the upper molar series from Pakefield. 

 They contain five out of the six molars, premolar 2 only being absent. 



* The remains of this species in the British Museum have now been largely 

 increased by the accession of all the type specimens in the possession of the late 

 Dr. Falconer. — January 1868. 



t Described in Dr. Falconer's notes, Palaeont. Mem. vol. ii. p. 354. 



I Described by Dr. Falconer, vol. ii. p. 360. 



