56 
The triangular expanded facial part of the upper end of each pre- 
maxillary intervening between the nasal and maxillary bones will 
always serve to distinguish the cranium of an immature Trogl. Goriila 
from that of a Trogl. niger. 
May 9, 1848. 
W. Yarrell, Esq., V.P., in the Chair. 
Letters were read from Captain Hope, R.N., dated Rio Janeiro, 
February 23, and from Mr. Bridges, Corr. Memb., dated Valparaiso, 
Feb. 27, 1848. 
The following communications were made to the Meeting :— 
1. Notice oF A NEW SPECIES oF MonkKEY FROM ANGOLA, LIVING 
IN THE GARDENS OF THE Society. By J. E. Gray, Esa., 
F.R.S. erc. 
(Mamm. pl. 3.) 
The Society has recently procured a Monkey from Angola, which 
bears some resemblance to the Diadema Monkey which M. F. Cu- 
vier erroneously described and figured as the female of Cercopithecus 
Diana, but it differs from that species in the lips being black, like 
the face, and only covered with very short whitish hairs ; and also in 
being much darker coloured; and this blackness has increased since 
it has been in the possession of the Society and obtained a better 
fur. At first sight I thought that it might be a melanism of some 
other species; but on comparing my notes with the specimens in 
the British Museum collection, I am convinced that it is different 
from any I have before had the opportunity of examining. 
It belongs to the division of the genus Cercopithecus with rounded 
whiskers formed of annulated hairs, which have no beard, a variegated 
fur, and black nose and lips, and is easily distinguished from the 
species of that division by its dark colour and broad frontal band. I 
propose to call it : 
The Pluto. Cercopithecus Pluto. 
Sp.ch. Black; the hair of the broad frontal band, ringed with 
white ; the large rounded whiskers, the back, the upper part of the 
front of the sides, and the base of the tail, ringed with varying 
greenish white; the distal half of the tail black; the face and lips 
black, with short, scattered white hairs. 
Inhab. Angola. 
This species is easily known at first sight by the deep black colour 
of the back of the head, and limbs, and the broad white frontal band: 
, the large mantle-like patch of minute, white, grisled hairs on the 
