It is described in the following manner, as coming from the district of Hainan:--“Yuen--male black, female white, like a Macaque, but larger, with the two fore-arms exceedingly long. Climbs to tree-tops, and runs among them backwards and forwards with great agility. If it falls to the ground it remains there like a log! Its delight is in scaling trees, as it cannot walk on the ground. Those desiring to rear it in confinement should keep it amongst trees, for the exhalations of the earth affect it with diarrhœa, causing death; a sure remedy for this, however, may be found in a draught made of the syrup of the fried foo-tse” (seeds of _Abrus precatorius_, the Indian liquorice). In a work called _Pun Yu liang che_, the various kinds of Yuens are mentioned which are known to the author. “There are three kinds of Yuens--the Golden-silk Yuen, which is yellow; the Jade-faced Yuen, which is black; and the Jet-black Yuen, which has the face also black. The Golden-silk and the Jade-face are both difficult to procure.” “Hainan has also the Rock Yuen; it is small, about the size of one’s fist. If allowed to drink water it grows in size. This is also called the Black Yuen, and is difficult to obtain.” “The word Yuen is given to them from their love of climbing and their wild disposition.” In Central Hainan the magistrate of the district was of opinion that the Yuen had the power of drawing its long arm-bones into its body, and that when it drew in one it pushed out the other to such an extraordinary length that he believed the two bones united in the body. He used the front bones of the arms for chopsticks. THE WOW-WOW. A species which is called the Wow-wow, or Silvery Gibbon (_Hylobates leuciscus_), is perhaps more interesting to the anatomist than to the observer of the habits of animals; for nothing is known about their method of living. Their skull shows a decided ridge or crest along the top, which branches well in front into two ridges going to the front over the orbit. Moreover, the chin of the lower jaw is very deep, the angles slightly turned in, and the eye teeth are thin and sharp. [Illustration: WOOYEN APE. (_From a stuffed specimen in the British Museum._)] THE AGILE GIBBON.[24] This animal is also interesting, from having a great twist inwards of the jaw behind, and two curious ridge-like crests on the head. Its name conveys the extreme agility of the animal, as observed in confinement.