MAMMALS COLLECTED IN SIAM. 341 
downwards, the latter slightly lengthened but not forming a pad or 
cap. 
Colour. Sides of face, chin and whiskers silvery, the latter 
slightly tinged with buff. Upper parts deep fuscous-grey ( the roots 
of the hairs deep mouse-grey ) much grizzled or frosted by the 
silvery tips of the hairs, the median line of shoulders and back 
darkest. Hair of shoulders and sides with neutral grey bases and 
silvery tips, that on the sides being longer and much paler. 
Outer sides of forelimbs less frosted on the upper arm than 
the shoulders, and gradually darkening over the forearm to clear 
black on the hands. Hind-limbs like the sides on their outer aspect, 
the front of the thigh darker; the lower leg very silvery; feet 
sharply contrasting, black very slightly grizzled. 
Throat, lower parts of body and inner sides of limbs buffy- 
silvery to pale neutral grey. 
Tail black thoughout and slightly grizzled, the upper surface 
darkest (when entirely unworn many more of the hairs probably 
have silvery tips ), base of the undersurface buffy-silvery. 
There is the usual sex-mark of the female:—a large white 
crescentic skin patch extending from below the callosities down the 
inner side of either thigh. 
Skull and teeth. Agree with those of P. germaini except that 
the ascending ramus of the mandible is narrower. 
Measurements. External measurements taken in the flesh :— 
head and body 495; tail, 795 ; hind-foot, s. u., 152; ear, 37. Skull :-— 
greatest length, 95 ; basal length, 68; upper tooth row excluding in- 
cisors (alveoli ), 29 ; zygomatic breadth, 70. 
Specimens examined, One, the type. 
Remarks. Our knowledge of the silvered leaf-monkeys is 
not complete, and the relationships of the various forms is still 
somewhat obscure, but the present animal is related to P. germaint 
which is really only a local form of P. cristata ( Raffles ). 
I have been able to examine a series of these monkeys from 
Indo-China and Malaysia; they are germaini from S. E. Siam; 
VOL. Tih, NO. 4°1919, 
