PYGATHRIX 51 



Type locality. Trong, Lower Siam. Type in United States Na- 

 tional Museum. 



Geogr. Distr. Lower Siam and southern Tenasserim ; Kisseraing, 

 and Sir William James Islands, Mergui Archipelago. 



Genl. Char. Of the P. obscura group, but legs from hips pale 

 smoke gray, and tail cream color. 



Color. Face bare, upper lip, and space over eye flesh color, 

 darker about nose and beneath eyes. Hairs on forehead long, upright, 

 and extending to ears brownish black; hairs on lips and lower cheeks 

 long, and extending backward beyond ears, blackish ; top of head and 

 nape yellowish white; dorsal line mummy brown, paler than black; 

 rest of upper parts and flanks black tinged with brown ; outer side of 

 arms very dark hair brown, with a reddish tinge on shoulders, and 

 grading into black on wrists and hands ; throat sparsely covered with 

 dark brown hairs ; under parts grayish brown ; outer side of legs smoke 

 gray, with a brownish tinge from knee to ankle ; feet blackish ; tail 

 uniform cream color. Ex type United States National Museum. 



Measurements. Total length, 1,257 ; tail, 724. Skull : total length, 

 94.7 ; occipito-nasal length, 77 ; Hensel, 66.5 ; zygomatic width, 70 ; 

 intertemporal width, 40.7 ; palatal length, 32.7 ; median length of nasals, 

 93 ; length of upper molar series, 24.4 ; length of mandible, 68.6 ; length 

 of lower molar series, 30. Ex type United States National Museum. 



This very distinct species can at once be recognized by its cream 

 colored tail and pale legs. The examples from the islands, of which 

 there are only a male and a female, differ slightly in certain particulars. 

 The legs are even paler than those of the type, hands and feet jet 

 black, strongly contrasted with the arms and legs, and the skulls have 

 a flatter braincase and broader rostrum. The material is hardly 

 sufficient to enable definite decision to be reached, and I leave these 

 island examples under the name of the present species, although they 

 may eventually prove to be worthy of a separate designation. 



Pygathrix ROBiNsoNi (Thomas) . 



Presbytis robinsoni Thos., Proc. Zool. Soc. Lond., 1910, p. 634. 



ROBINSON'S LANGUR. 



Type locality. Ko-Khan, Trang, Northern Malay Peninsula. 

 Type in British Museum. 



Genl. Char. Color white, dark beneath. Occipital hairs directed 

 forward, hairs on forehead radiating from points on temples ; median 

 crest present. 



