156 HYLOBATES 



manent, as the white hands and feet of H. lar, but no dependence can 

 be placed upon the general hue of the pelage at any time. Uniformity 

 of coloring is not one of the tenets of the species of Hylobates, and 

 so far as the hues of their coats are concerned each one wears whatever 

 seems best in his own eyes. The quantity and depth of color pigments 

 among the members of the different species is a most uncertain quality, 

 and rarely do two individuals possess them in the same degree, other- 

 wise these many and extreme variations are quite unaccountable. 



Mr. Pocock states that the voice of the Hainan Gibbon "is quite 

 different from that of the Hoolock. It has a high pitched trill all on 

 the same note, and shriller even than the high note of the Hoolock's 

 cry. It consists of from about three to six distinct cries repeated in 

 very rapid succession, suggesting almost production by vibration of 

 the tongue, although as a matter of fact, I believe the lips alone are 

 instrumental in producing the effect. There is then a momentary 

 pause, after which the cry is repeated. It may perhaps be represented 

 in the following way: hoo, hoo, hoo, hoo — hoo, hoo, hoo — hoo, 

 hoo, hoo, hoo — etc. The Hoolock on the contrary cries as follows: 

 hah, hoo, hah, hoo, hah, hah, hoo, hah. The 'hoo' is on a lower 

 note than the 'hah,' with which the cry frequently ends. 



"The ordinary expression of anger or remonstrance in the Hainan 

 Gibbon is a prolonged and guttural grunt, which is repeated rapidly 

 and often, and frequently interspersed with a kind of warble when 

 the excitement rises. 



"Both the Hoolock and Lar Gibbon in the Gardens drink habit- 

 ually by dipping the back of the hand and knuckles into the dish and 

 licking the water off. They do not scoop it up in the strict sense of the 

 word at all. The Hainan Gibbon, on the contrary, almost invariably 

 drinks direct with her mouth, only very rarely using her left hand for 

 the purpose. It is possible she may have abandoned the habit of 

 employing the hand at the time when an injury deprived her of the 

 use of her right arm, and since the left is frequently occupied in sup- 

 porting herself upon the bars or perches in the cage, she has no hand 

 available for the purpose of drinking without quitting her hold." 



Hylobates hoolock Harlan. 



Simia hoolock Harlan, Trans. Amer. Phil. Soc, IV, New Ser., 

 1834, p. 52, pi. II. 



Hylobates choromandus Ogilby, Proc. Zool. Soc. Lond., 1837, p. 

 689; Waterh., Cat. Mamm. Mus. Zool. Soc. Lond., 1838, 

 p. 3 ; Less., Spec. Mamm., 1840, p. 54 ; Martin, Mammif . 



