THE AGILE GIBBON. 



35 



This mode of employing the two sets of limbs is well shown in the Gibbons, and in 

 order to fit them in the best manner for their arboreal existence, the thumb of the 

 fore-hands is found to be almost destitute of the muscular prominence which is pop- 

 ularly known as the " ball " of the thumb, is therefore incapable of grasping, and can 

 only follow the direction of the fingers ; while the corresponding member on the 

 hinder hands is very large and powerful in proportion. 



All the Gibbons are gifted with voices as powerful as their limbs, and the creatures 

 seem to lose few opportunities of exercising lungs or limbs. The cry which these an- 

 mals utter is a singular one, loud, and piercing, and has been represented by the 

 syllables " wou-wou," which duplex combination of intonations is often used as a general 

 name common to the whole family. Some writers express the sound by the words 

 " oa-oa," and others as " woo-woo," among which the reader is left to choose. 



The several species of Gibbon do not seem to inhabit the same localities, although 

 they all, without an exception, live among trees. Some reside among the mountainous 

 ranges and their forests of fir-trees, while others prefer the lower regions of the wooded 

 plains and valleys. All, however, agree in their exceeding activity and noisy voices, 

 thus proving themselves in every way to be worthy types of their mythological 

 lineage. 



All animals which are destined to move with great rapidity, bear a sure sign of their 

 destiny in the configuration of their bodies. Active exertions cause the heart to beat 

 so fiercely, and the blood to circulate with such rapidity, that a provision must be 

 made to give the blood a sufficiency of air to refresh it after its hard labor. This can 

 only be done by the gift of very large lungs with plenty of room for their free action. 

 Accordingly, the frames of all swift animals are found to be made on a similar model, 

 although necessarily modified according to the description of animal. 



Thus, among the well-known living creatures with which all are familiar, we may 

 cite the greyhound and the racehorse. Or if we turn to the birds, the falcons and 

 swallows are good examples of this formation of body. The chest and fore-part of 

 the body are wide and capacious, in order to accommodate the large lungs which are 

 necessary for the creature. The limbs which aid the progress of the animal, whether 

 it be bird or beast, are very largely developed, while the subordinate parts of the 

 body and limbs are reduced to the smallest size compatible with the well- 

 being of their possessor. A greyhound in proper 

 health, and ready for the course, has not an ounce 

 of superabundant weight about it ; neither, has 

 the racehorse when at the post. So with the 

 falcons and swallows, until we come to the hum- 

 ming-birds, which exhibit this modification of 

 limb and body in singular perfection. 



The Gibbons are formed on a model of a sim- 

 ilar nature, their enormously long arms and broad 

 shoulders contrasted with the smaller hinder 

 limbs and thin flank showing that they are capable 

 of rapid movement, while the deep and capacious 

 chest gives indication that they can endure a long 

 continuance of labor without being exhausted 

 by it. 



Of the habits of the Gibbons in a wild state, 

 very little is known, as they are shy in their nature, 

 and by means of their wonderful agility escape 

 among the trees in a manner that baffles pursuit or 

 observation. As to the species which is repre- 

 sented in the accompanying engraving, it seems to 

 be the most active of this agile family, and well deserves the name that has been given to 

 it. Rather more has been noticed of this wonderful creature, and a further insight 

 into its habits has been gained by means of a female specimen, which was captured 

 and brought safely to London, where it lived for some time. 



AGILE GIBBON. -Hylobates Agills. 



