450 PROF. AV. H. FLOWER ON THE CRANIAL AND [May 16, 



and figured by Dr. Gray in the paper above referred to as R.floweri, 

 and called in the Catalogue of the Museum of the College of Surgeons 

 R. sumatrunus, is a very characteristic specimen of R. sondaicus, 

 belonging perhaps to what Blyth would call the narrow type of that 

 species. It was presented by Sir Stamford Raffles together with the 

 Sumatran specimens, though no locality is recorded for this indivi- 

 dual. This circumstance probably occasioned its being entered in 

 the Catalogue as R. sumatranas', for although it is not certain that it 

 came from Sumatra, it is quite probable, as we have now other reasons 

 for believing that R. sondaicus is an inhabitant of that great island. 

 The two skulls in the British Museum (supposed to be from Borneo) 

 described by Dr. Gray as R. nasalis also present, in my opinion, no 

 characters by which they can be distinguished from R. sondaicus, 

 while on the other hand his R. stenocephalus is a young example of 

 R. unicornis, or at all events has all the essential characters of that 

 species as distinguished from R. sondaicus. The specific distinctions 

 relied upon by Dr. Gray, the narrowness and rounding of the upper 

 surface of the skull, appear to me far too liable to individual variation 

 to constitute valid characters without other evidence *. 



A skeleton, lately received at the British Museum, through Mr. 

 Franks, of Amsterdam, from Sumatra, is R. sondaicus, thus afford- 

 ing confirmatory evidence to that already obtained t of the presence 

 of both the two-horned and one-horned species in that island. 



A still more interesting circumstance, as enlarging our knowledge 

 of the geographical distribution of these animals, is, that the young 

 skull obtained from Borneo by Mr. Low, of Labuan, added last year 

 to the British-Museum collection, and of the habitat of which there 

 is not a shadow of uncertainty, as in the case of the other supposed 

 Bornean skulls in the same collection (which are R. sondaicus), be- 

 longs to the two-horned species or R. sumatrensis. This fact, with 

 that lately recorded by Mr. Sclater J, of the occurrence of this form 

 in Assam, give the two extremes at present known of its range. 



A question has lately arisen whether there may not be two species 

 of Asiatic two-homed rhinoceroses. Cuvier already believed that 

 there were two varieties in the island of Sumatra, distinguished by 

 their size ; but the question has been brought into prominence by 

 the presence in our gardens of two living animals of the same sex, 

 one from Chittagong, and one from the southern part of the Malay 

 peninsula, presenting such differences of size, colour, length of tail, 

 and distribution of hair, that they would strike any zoologist as 

 being examples, if not of different species, at least of very well marked 

 varieties. In the former light they have been regarded by Mr. 

 Sclater, who has bestowed the name of R. lasiotis, or Hairy-eared 



* Mr. Busk (P. Z. S. 1869, p. 413, foot-note) has already recorded his opinion 

 that all these three species of Dr. Gray are indistinguishable from li. sondaicus. 

 As regards the first two, as will be seen above, 1 am of the same opinion, but 

 not as regards the third. 



t The teeth brought by Mr. Wallace and described by Mr. Busk, and the 

 probability of the skull presented to the College of Surgeons by Sir T. RafBes 

 being from that island. 



j P, Z. s. L875, p. 566. 



