MAMMALS COLLECTED IN SIAM. 347 
The specific name for the crab-eating monkey of S. E. Asia 
and the Malay Islands is Macaca irus Cuvier (syn. fusciculuris Raffles, 
vide Cabrera, Ann. and Mag. Nat. Hist. (8) VI, p. 620). I have not 
seen sufficient material from Sumatra (typical locality ) to show 
whether the animals of the mainland are subspecifically distinct; a 
fairly large collection of the latter, however, may be divided rough- 
ly as follows :— 
1. Of twenty-five examples from the Malay Peninsula north 
of Lat 9°, Tenasserim, East and South-east Siam, and small islands 
off the coasts, all are dull-coloured animals having no tone of bright 
ochraceous in their upper parts. 
| 2. Of forty-five specimens from the Peninsula south of Lat. 
8° and neighbouring small islands, the majority (especially regarding 
the islands) have a decided ochraceous tone on the head and back, 
sometimes so intense as to be ferruginous: but there are a few 
which are indistinguishable from northern examples 
Such a distinction, however, seems to be of no value; as 
Blanford states that both dark coloured and golden rufous animals 
are found in Burma; it is from one of the latter that M. aureus Is. 
Geoffr., is described. 
Elliot has given names to a number of macaques recently : 
Pithecus capitulis seems to have been based merely on a very large 
specimen from Trang, Peninsular Siam, and a topotype can be 
exactly matched by an example from Singapore, to animals from 
which island the same author has given the name. Pithecus dollmanni. 
Pithecus validus “is stated to have come from Cochin China,” and 
P. vitiis is attached to a specimen from Domel Id, Mergui Arche- 
pelago. 
6. Macaca irus atriceps, subsp. nov. 
Type. Adult male (skin and skull) No. 2283/C.B.K. Collect- 
ed on Koh Kram Id. near Cape Liant, S. E. Siam on 30th October 
1916. 
Characters. A very distinct race of M,. irus Cuv., with much 
black in the pelage, a black area on the crown and the basal half of 
the tail blackened above. A slight occipital crest. Bare skin of 
VOL. III, NO, 4, 1919. 
