1875. ] IN THE SOCIETY'S COLLECTION. 419 
assamensis, or at any rate with the specimen which I determined as 
such (P. Z. 8S. 1871, p. 222), aud which is the type of M. proble- 
maticus, Gray (Cat. Monkeys, p. 128), and is now in the British 
Museum. The fur is rather more reddish in tinge, and the tail is 
rather shorter*; but I am on the whole of opinion that the two 
specimens belong to the same species. 
3. ATELES MELANOCHIR. (Plates XLVIII. & XLIX.) 
The Black-handed Spider Monkey, as we call it, is now the com- 
monest species of the genus which we receive alive, our correspondents 
of the West-Indian Mail Service bringing many specimens from the 
Central-American Ports. They exhibit great variations in colour, as 
will be seen from the skins now before us, and from the drawings 
by Mr. Keulemans of four individuals living in the Monkey-house in 
January last, which I exhibit. They seem to vary between the form 
designated 4. ornatus by Dr. Gray, of which I have already given a 
figure (P. Z.S. 1871, pl. xv.), and the nearly uniformly grey form 
with black hands and feet, which Dr. Gray (Cat. Monkeys, p. 44) 
has called A. albifrons. 
The problem is whether these different forms are confined to 
different localities, or whether they occur together in the same dis- 
trict. To settle this a large series from different localities in Central 
America should be examined, which as yet I have had no opportu- 
nity of doing. But all the light-grey specimens with black hands 
and feet (such as that figured Plate XLVIII. fig. 17) are, so far as 
I can ascertain, from Nicaragua or Panama; and the dark form 
(Ateles ornatus) alone, as Mr. Salvin tells me, occurs on the Pacific 
coast of Guatemala. I am inclined to believe, therefore, that we have 
here to deal with a series of local forms of a ‘‘ not yet differentiated ”’ 
species. 
4. Hapate MELANURA. (Plate L.) 
Tacchus melanurus, Geofir. Ann. d. Mus. xix. p. 120 (1812). 
Hapale melanura, Wagner, Saugeth. i. p. 127 et v. p. 127. 
Mico melanurus, Gray, Cat. Monkeys, p. 64. 
On Nov. 9th of last year we purchased of a dealer a Marmoset in 
bad condition, which at the time I took for Hapale argentata (Linn.), 
_and so entered it in the register. It turns out, however, now that 
it has got clean and in good trim, to belong to the-nearly allied and 
almost equally rare H. melanura, of which we have never previously 
received a living specimen. Mr. Keulemans’s figure (Pl. L.) gives 
a correct likeness of this peculiar species{. 1 likewise exhibit a skin 
of it obtained by Natterer in October, 1826, at Matogrosso in the 
interior of Brazil, from my own collection. 
* Long. corp. 18 poll., caudze 7. 
+ This and a similar specimen received at the same time (both females) were 
obtained by the late Mr. Richard Avery Rix, Medical Officer to the Chontales 
Mining Company at St. Domingo, near Libertad in Nicaragua, in 1873, and were 
presented to the Society by his father, Mr. S. W. Rix, in July 1874. They are 
still living in good health in the Society’s Monkey-house (P. L. S., July 1st, 1875). 
+ Wagner's figure (Saugeth. y. pl. 13) is not at all good. an 
