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NOTES ON THE HABITS OF THE HOOLOCK. 

 By Geo. Candler, (m. b.) Cantab. 

 The Hoolock (Hylobates hoolock) is one of the most interesting of the family 

 Simiidce, and is perhaps not so familiar to naturalists at home as are some other 

 members of the family, as, owing to its extreme delicacy and the great difficulty 

 experienced in keeping it alive in confinement, it does not often find its way into 

 European collections. Even in the Calcutta Zoological Gardens it is difficult to 

 keep Hoolocks alive for any length of time. They often succumb to pneumonia, 

 or if they escape actual disease they mope and die from the effects of confine- 

 ment, or possibly from deprivation of some article of diet which in the wild state 

 they have been accustomed to. I have ventured, therefore, to submit to the 

 Society these short notes, made from the point of view of a field-naturalist 

 rather than from a scientific aspect. 



The Hoolock is clothed all over with a fine soft hair, which, perfectly black 

 in the male, in the female shows a greyish tint, especially over the back. This 

 uniform dark colour is only relieved by narrow horizontal streaks of white hair 

 above the eyes. The face, palms of the hands, and soles of the feet are devoid 

 of hair, and here the black skin is smooth and finely wrinkled and as soft as the 

 finest kid. 



The hallux and pollex have a flattened nail, the remaining digits have the nail 

 laterally compressed and resembling a claw. 



There is no tail. Ischial tuberosities and cheek-pouches are absent. 

 When the ape is sitting, the vertebral column presents a single marked curve 

 with the convexity backwards. On the ground the Hoolock has a very charac- 

 teristic gait. He goes along in a sort of shambling waddle, with legs bowed and 

 knees bent, the soles of his feet applied flat to the ground with the hallux 

 widely abducted, both arms being carried upwards and extremely abducted as if 

 to balance himself. He cannot get up any speed, and invariably swings up into 

 the first tree he comes to, where his movements are suddenly changed from 

 extreme awkwardness to extraordinary grace and agility. 



He swings along to the thinnest part of a bough, or to the slender end of a 

 bamboo, until it bends to his weight, then with a swing and a sort of a kick-off 

 he flies through the air, seizing another bough and swinging along it with the 

 unerring accuracy of a finished trapeze performer. I fancy he does very little 

 walking in the wild state, for I have never seen a wild Hoolock on the ground. 

 Moreover, they are only found in the dense jungle where the ground is every- 

 where covered by tangled vegetation. It is puzzling to me why these anthro- 

 poids, being so entirely arboreal in habit, should ,be lacking in such a useful 

 appendage as a tail. T think, at any rate, that it points to the fact that the apes 

 have been developed along a line distinct from the monkeys, the earlier traces 

 of which line are yet to be discovered . 



The Hoolocks are extremely shy, and it is most difficult to watch them, as they 

 are concealed by leaves high up in the tops of the bamboo-clumps or forest trees. 

 You may hear their cries all round you as you ride quickly along a jungle-tract, 



