There is good testimony that various species of Gibbon readily take to
the erect posture. Mr. George Bennett,* a very excellent observer, in
describing the habits of a male 'Hylobates syndactylus' which remained
for some time in his possession, says: "He invariably walks in the
erect posture when on a level surface; and then the arms either hang
down, enabling him to assist himself with his knuckles; or what is more
usual, he keeps his arms uplifted in nearly an erect position, with the
hands pendent ready to seize a rope, and climb up on the approach of
danger or on the obtrusion of strangers. He walks rather quick in the
erect posture, but with a waddling gait, and is soon run down if,
whilst pursued, he has no opportunity of escaping by climbing.... When
he walks in the erect posture he turns the leg and foot outwards, which
occasions him to have a waddling gait and to seem bow-legged."

{footnote] *'Wanderings in New South Wales', vol. ii. chap. viii.,
1834.

Dr. Burrough states of another Gibbon, the Horlack or Hooluk: "They
walk erect; and when placed on the floor, or in an open field, balance
themselves very prettily, by raising their hands over their head and
slightly bending the arm at the wrist and elbow, and then run tolerably
fast, rocking from side to side; and, if urged to greater speed, they
let fall their hands to the ground, and assist themselves forward,
rather jumping than running, still keeping the body, however, nearly
erect."

Somewhat different evidence, however, is given by Dr. Winslow Lewis:*

"Their only manner of walking was on their posterior or inferior
extremities, the others being raised upwards to preserve their