5. HYLOBATES. 11 



Ouko, Tabraca, Hist, de Siam, ii. p. 308, 1771. Ilylobates pileatus, 

 Gray, Five. Zoul. Soc. 18G1, p. 13G, t. 21 ! 



Var. 1. Black. B. M. 



Va7\ 2. Dirty white ; crown, whiskers, and belly black. B. M. 



Var. 3. White; crown-spot and belly l)lack; whiskers white. B. M. 



Var. 4. WTiite, except the black bristles on the eyebrow. B. M. 



ilab. Siam, Moithot. 



3. Hylobates leucogenys. The White-cheeked Gibbon. B. M. 



Black ; throat and sides of cheeks with a broad white spot of 

 spreading rigid haii's ; forehead black, without any frontal baud. 



Hylobates leucogenys, Oyilbi/, Froc. Zuvl. Soc. 1840, p. 20 ! Martin, 

 Monkeys, p. 445, t. ! 



Hub. . 



4. Hylobates hoolock. The Imlian Hylobates. 



Black ; froutal band grey ; whiskers soft and fluffy, black or 

 greyish black. 2j_ jj 



Siuiia hoolock, Harlan, Trans. Amer. Phil. Soc. iv. p. 52, 1834; Is. 

 Geoff. Hylobates hoolock, Lesson ; Martin, Monkeys, p. 438, f. 274, 

 2/5. Hylobates scyi-ites, Oyilbyl 



Var. ? Fur brownish. g ]y[ 



Hylobates fuscus, Zetvis, Boston Journal N. H. i. p. 33. 



Var. Fur pale yellowish-brown; frontal band white; whiskers 

 bushy, darker brown. 



Hylobates choromandus, Oyilby, Proc. Zool. Soc. 1837, p. 68 ! Martin 

 Quad. 442, f. ! ' 



Hub. India : Himalaya Mountains, Hardwiche. 



5. Hylobates Rafflesii. The Malay Gibbon. B. M. 



Black ; frontal band white ; whiskers soft and flufty, full black. 

 Simia lar, Paffies, Trans. Linn. Soc. xiii. p. 242. Hylobates Rafflesii, 

 Gioff. ; F. Ciiv. Mamm. Lith. ; 7s. Geoff. Ilylobates agihs, var., 

 Martin Quad. p. 425, t. ! Hylobates coucolor, Harlan, Journ. 

 Acad. A. S. Fhilad. V. p. 229. Hylobates Harlaui, Lesson. 



Ilab. Sumatra. 



Var. Dark brown ; frontal band distinct. 

 Ilylobates coucolor, S. Miillvr, Verhand. t. ! (not Harlan). Hylo- 

 bates Mulleri, Martin, MonJccys, i. p. 4 ; 7s. Geoff. 

 Hah. Borneo. 



Dr. Dahlbom describes the skeleton, which has the bladebonc 

 smooth, without any tubercles. 



