l56 MR. OLDFIBLD THOMAS ON [Juue 4, 



12| ; interorbital breadth 8. [Teeth and palate too much diseased 

 for measurement.] 



From these measurements it appears that R. lasiotis exceeds 

 considerably the equally aged skull of '* O.niger" (Flower's No. 2) 

 from Malacca, and is only approached by No. 5 (R. C. S. No. 2142), 

 said to be from Sumatra. 



Allowing for its much more youthful couditiou, the latter skull is 

 practically of the same size as the Chittagong one, and therefore, 

 if it really came from Sumatra, disposes at once of the claim of 

 li. lasiotis to distinction on the gi'ound of size. 



But I am not satisfied about the question of locality, for 

 Sir Stamford Baffles, as a collector of Natural History objects, and 

 a great Governor and Administrator, might easily have had 

 brought to him a skull from any part of the East Indies ; so that, 

 merely on the evidence of this skull only, I do not like to dismiss 

 the claims of B. lasiotis to distinction, since such dismissal would 

 carry with it the assumption, otherwise unsupported, that the 

 skulls o£ the Sumatran Rhinoceros vary in size to so considerable 

 an extent. 



The Pegu skull (Theobald, B.M. No. 68.4.15.1, Flower's No. 4) 

 is intermediate in size, as in locality ; while all the Malaccan and 

 other Sumatran skulls are comparatively small, as are those from 

 Borneo. 



For the time being therefore, on the assumption that the Raffles 

 skull referred to was not really from Sumatra, 1 should consider 

 R. lasiotis as a tenable northern subspecies of R. sumatrensis, 

 characterized mainly by its greater size. As noted by Flower in 

 the case of the Pegu skull, and borne out by that from Chittagong, 

 the post-glenoid processes appear to be longer in proportion than 

 in the Malaccan and Sumatran Rhinoceros. 



Of course it follows, from the tentative nature of this conclusion, 

 that further material is badly wanted, both from the North, to see if 

 the form found there is constantly larger, and from Sumatra, to see 

 if any such skull as R. C. S. No. 2142 may really occur there. 



Further material may also prove that the typical horn of Gray's 

 " Rhinoceros crossii " belongs to the northern subspecies, in which 

 case the name crossii will have to supersede lasiotis. But this 

 identification is as yet too doubtful to be definitely accepted. 



Now with regard to the general question of the nomenclature of 

 Rhinoceroses and the genera in which the recent species should 

 be placed, I would draw attention to the recent important paper 

 by Prof. Osborn on the " Phylogeny of the Rhinoceroses of 

 Europe " ^ 



^ Bull. Amer. Mus. N. H. xiii. p. 229 (1900). I should demur to the charac- 

 terization of B. bicornis as a dolichocephalic form, for its short stumpy head is 

 one of its most marked distinctions from its long-headed congener i?. 6m2te% but 

 in all other respects Prof. Osborn's conclusions seem justified. In conjunction 

 with Mr. Lydekker, I have compared the fine skull in the Museum of R. platy- 

 rhinus, hitherto usually considered related to the sinuis group, and after careful 

 consideration we have come to the conclusion advocated by Osborn, that, in spite 

 of its tooth characters, it is really most nearly allied to the sutnatrensis grouij. 



