siamang (Symphalangus syndactylus) English: Plate XXXVIII. Siamang Gibbon Hylobates syndactylus.
Date 1897
Source Handbook to the Primates, Vol. II. http://archive.org/details/handbooktoprimat02forb
Author Henry Ogg Forbes (1851-1932). Species Plates by John Gerrard Keulemans (1842–1912).
Source: https://commons.wikimedia.org/wiki/File:Handbook_to_the_Primates_Plate_38.jpg
The siamang (Symphalangus syndactylus) is an arboreal black-furred gibbon native to the forests of Malaysia, Thailand, and Sumatra. The largest of the gibbons, the siamang can be twice the size of other gibbons. The siamang is the only species in the genus Symphalangus.