108 Mr. Vigors and Dr. Horsfield 



15. In these dimensions our specimen falls far short of Simla Lar ; but 

 we imderstand that specimens of our animal are often found of much 

 greater size than that before us. 



The second specimen in the Sumatran collection, to which we have 

 alluded, accords generally with that just described in its size and markings; 

 disagreeing with it only in colour, being of a light brownish gray, where 

 that of the other is black. This specimen may probably be the female, or 

 the young of the same species. Its general colour is similar to that which 

 predominates in Simla agllls, and in the alleged species S. variegata. It 

 is a subject well worth the consideration of those naturalists who reside in 

 the native country of these animals, to determine whether these differences 

 of colour are, , on the one hand, owing to the changes that take place in 

 the same individuals, or to the difference in sex : or, on the other hand, 

 whether they really indicate a difference in species. We know that a 

 material change in colour does take place in some species. We have 

 a series of the Semnoplthecus cristatus now before us, in which the young 

 is of a bright yellowish colour; a more adult individual of the same colour, 

 but with the head and hands iron gray ; and the adult of a uniform iron 

 gray. It is to be observed, that in this last species the extreme members 

 first assume the appearance of the adult ; while, on the contrary, in the 

 species which we have named albimana, the body, not the extreme 

 members, has the adult appearance, if we suppose the animal to be the 

 young of Simla Lar. 



We do not feel satisfied with the generick names given to this group. 

 The Linnean term Simla has been latterly entirely rejected in the sub- 

 divisions of the family. We would suggest whether this term might not 

 with propriety be retained for the entire group oiApes, and without any 

 farther subdivision. At present there are four genera proposed for this 

 very limited group; — Troglodytes^ Geoff., Plthecus, Cuv., Hylobates, 

 111., and Pongo, Lacep. The Chimpanzee which stands singly as the 

 representative of Troglodytes, — a name, by the way, which has been 

 equally appropriated to Ornithology, — may perhaps be vnth propriety 

 separated as exhibiting a strikingly distinguishing character in its short 

 arms. The difference however between Slmlce Satyrus and syndactyla, 

 and SimicB Lar, agills, leuclsca, &c., consisting solely in the absence or 

 presence of naked callosities, appears to us too trivial to form the ground 



