Gibbons agree with the larger man-like apes in the complete absence of the tail, but are distinguished by the great length of the limbs, more especially the front pair, so that when these curious pigmies are standing upright on their feet, their hands touch the ground. It is very interesting to note in this connection that gibbons are the only man-like apes which habitually assume the erect posture in walking, when the arms are usually elevated and in some cases extended horizontally, thus giving a most remarkable appearance to their owners. All the members of the group are confined to tropical south-eastern Asia, where they range from the eastern portion of the Himalaya through Burma and the Malay countries to the island of Hainan, off the southern coast of China. The largest species, the siaman (_Hylobates syndactylus_) of Borneo, does not much exceed one yard in height. In colour they are very generally black, often, as in the species represented in the Plate, with a narrow white band or fillet surrounding the greater part of the face, or making merely a line above the eyebrows. In the white-handed species, forming the subject of the illustration, the white fillet attains its fullest development, and the hands and feet are likewise white. This species inhabits the mountain-forests of Tenasserim at elevations between three thousand and five thousand feet, whence it extends through the Malay Peninsula. Its near relative the hulok (_H. hulok_), whose range extends from Assam to Arakan and the neighbouring districts, lacks the white hands and feet, while the fillet on the face merely forms a band over the eyebrow. In the Hainan gibbon (_H. hainanus_) even the eyebrow-band is wanting. A specimen of this last-named species, which is very near akin to the hulok, afforded a surprise to naturalists in that it changed the colour of its coat during its sojourn in the London Zoological Gardens. When obtained in 1897, at an age of about six months, its colour was dark smoky grey, but this soon changed to black, which persisted till after the animal’s arrival in London in January 1904. In February of that year the fur began to assume a greyish tinge; and by autumn the entire coat had become silvery, or stone, grey, except for a black stripe down the middle line of the head. It does not, however, appear that this colour-change is universal in the species; for another captive specimen believed to be about a dozen years old was wholly black. [Illustration] This is confirmed by the observations of a French traveller in the case of the white-cheeked gibbon (_H. leucogenys_) of Annam and Siam, in which two distinct colour-phases are noticeable.