RHENOPITHECUS 105 
the Mékong in the vicinity of Yerkalo, Atentsé and Tsékon. It is 
certain that along the straight and elevated crest that separates the 
Mékong from the Yantze-kiang in the places that are nearest to their 
course, it is found in large troupes. It may be supposed that these 
Rhinopithéques inhabit both sides of this chain, but at different 
seasons; in summer they would frequent the side towards China, 
and descend eastward towards the right bank of the River Blue; 
these would be the great black Monkeys mentioned by M. L’Abbé A. 
David; in winter, on the contrary, they would take up their abode on 
the western slope towards Thibet, and limited to the valley of the 
Mékong, as is proved by the period in which our specimens were killed 
by Mgr. Biet’s hunters, several months after the last of August, 
the date of the passage of Prince Henry of Orleans from Tsékon. 
This last locality apparently is the approximate meridian limit of 
their domain; but to the northwest they must go quite near the 
_Thibetan Province of Kham, both M. Bonvalet and Prince Henry 
of Orleans having seen them during their passage of the Tengri-Nor 
at Batang. Finally, to the east, the River Blue would probably be 
the natural barrier separating them from R. roxellane, their relative 
of the Principality of Moupin, and south of the Province of Kansu.” 
RHINOPITHECUS BRELICHI Thomas. 
Rhinopithecus brelichi Thos., Proc. Zool. Soc. Lond., I, 1903, p. 
224, pl. XXI. 
BRELICH’S LANGUR. 
Type locality. Unknown. Type in British Museum. 
Geogr. Distr. Van Gin Shan range of mountains, north of the 
Province of Kwei-chow, 108° E. 29° N., Central China. 
Genl. Char. Size very large; fur on flanks longest; oval white 
patch between shoulders; tail very long. 
Color. Crown and cheeks yellowish, hairs tipped with black; 
nape black, hairs broccoli brown, black tipped; hind neck, hairs brown- 
ish with black tips; large white patch between shoulders, hairs white 
to roots ; upper part of body and flanks slaty gray; sides of neck, hairs 
pale orange tipped with black, the orange deepening in color as it 
goes towards the shoulders and inner side of arms; outer side of 
arms black; outer side of thighs silvery gray, legs below knees black; 
inner side of limbs yellowish white, becoming orange next to the 
black on inner side; throat black, hairs being gray, black tipped; under 
parts of body ashy gray; tail very long, black for the entire length, 
and with a small white pencil at tip; ears black, the edges all around 
