178 SYMPHALANGUS 



throat; second and middle toes united by web up to first joint; supra- 

 orbital ridges of skull well developed, occipital region truncate. The 

 brain in the young has the cerebellum completely covered by the cere- 

 brum ; but in the old animal the cerebellum projects beyond the cere- 

 brum posteriorly. 



Color. Black. 



Measurements. Skull: total length, 139; occipito-nasal length, 

 104.5 ; Hensel, 101 ; zygomatic width, 92 ; intertemporal width, 56.7 ; 

 median length of nasals, 12.8; length of upper molar series, 35.3 ; length 

 of mandible, 94; length of lower molar series. 40.9. 



If the S. s. continentis Thomas, eventually proves to be a distinct 

 race of the Sumatran species, then it is not at all probable that this 

 species is to be found anywhere on the Malay Peninsula. 



The Sumatran animal is very large, in fact the greatest of all 

 the Gibbons in size, and individuals from South Pagi Island and the 

 Malay Peninsula differ from it only in size, and this is relative, the 

 Malaccan Gibbon being intermediate, the one from South Pagi Island 

 being the smallest. 



Mr. Forbes (1. c.) gives an interesting account of one of these 

 Gibbons he had in Sumatra from which the following is taken: "Its 

 expression of countenance is most intelligent and often very human ; 

 but in captivity it generally wears a sad and dejected aspect, which 

 quite disappears in its excited moods. * * * Jt will never put 

 its lips to a vessel to drink, but invariably lifts the water to its mouth 

 by dipping in its half-closed hand and then awkwardly licking the 

 drops from its knuckles. It generally sits with its arms crossed over 

 its chest, and its fingers overlaid behind its head. * * * Although 

 it often inflates its laryngeal sac, it rarely gives utterance to more than 

 a yawn-like noise or suppressed bark ; but this dilatation has no 

 reference apparently to its good or bad temper, although when very 

 eager and impatient for anything, a low pumping bark is uttered. 

 Every evening it makes with me a tour around the village square, 

 with orte of its hands on my arm. It is a very curious and ludicrous 

 sight to see it in the erect attitude on its somewhat bandy legs, hurrying 

 along in the most frantic haste, as if to keep its head from outrunning 

 its feet, with its long free arm see-sawing in a most odd way over its 

 head to balance itself, and now and again touching the ground with its 

 finger tips or knuckles. That they can leap the great distances from 

 tree to tree ascribed to them is no doubt an accurate observation ; 

 but they appear to be sometimes terror-stricken and unable to perform 



