a genus of the family hylobatidae consisting of six species. The members of this genus inhabit rain forests in southeast asia. They are arboreal and differ from other anthropoids in the great length of their arms and very slender bodies and limbs. Their major means of locomotion is by swinging from branch to branch by their arms. Hylobates means dweller in the trees. Some authors refer to symphalangus and nomascus as hylobates. The six genera include: h. Concolor (crested or black gibbon), h. Hoolock (hoolock gibbon), h. Klossii (kloss's gibbon; dwarf siamang), h. Lar (common gibbon), h. Pileatus (pileated gibbon), and h. Syndactylus (siamang). H. Lar is also known as h. Agilis (lar gibbon), h. Moloch (agile gibbon), and h. Muelleri (silvery gibbon).