TEE SIAMANG. 
75 
One day, however, it bit me so sharply while giving it food that I lost patience, and gave it rather a 
severe beating, which I regretted afterwards, as from that time it disliked me more than ever. It would 
allow my Malay boys to play with it, and for hours together would swing by its arms from pole to 
pole, and on to the rafters of the verandah, with so much ease and rapidity, that it was a constant 
source of amusement to us. When I returned to Singapore it attracted great attention, as no one had 
seen a Siamang before, although it is not uncommon in some parts of the Malay peninsula.” 
There are some interesting points about the relation of the construction of this animal and its 
method of moving. Thus, in grasping a bough with the arm at full length above the head, so as to leave 
it with a swing in order to grasp another rapidly and for a correspondingly short period of time, the 
fingers require to be kept together as much as is possible, and to remain more or less bent on the palm. 
The long thumb may or may not be used, but in order to move efficiently it must be free, and also 
strong. Now in the Siamang these necessary peculiarities are present, and the common use of 
the finger and thumb in taking hold of things in the ordinary manner is sacrificed to them, and there is 
little or no delicacy of fingering or of prehension. Moreover, the fingers and thumbs are extremely 
thin and delicate, and in order to render the first finger less movable, it is, to a certain extent, deficient 
in its muscles of extension ; and the common bending or flexor muscle of the Angel'S is very inde- 
pendent of that of the thumb. In compensation there is a special muscle found in this genus alone, 
which pulls the top of the second finger towards the thumb. * The skeleton of the hand shows that 
the fingers are slightly curved. There is no doubt that the hand of the Siamang, although it has these 
peculiar muscles, the curve of the bones, and also the extra bone noticed in the Orangs, is, as far as its 
skeleton is concerned, much more human than that of the other Apes. The extensor muscles of the 
fingers resemble those of the Orangs. The hand is larger than the foot in these animals, and the fore- 
arm is much longer than the upper arm. 
A French naturalist states that the animal can leap, or, rather, swing — for it is done with the fore 
limbs — with graceful agility at least eighty feet, and the muscles of the ami, which are connected 
with the chest, aid in this. The pull is from the stationary arm — to the chest of the movable 
body by muscular contraction ; and the greater the muscular connection between the arm and chest, 
the greater will be the movement. In order to provide for this, the great muscle of the front of the 
upper arm, the biceps (see page 26), is not only attached, as in the other Apes and in man, to the 
blade-bone just above the arm-joint, but also to the chest in front, for it is united there with the 
great muscle which springs from the ribs and breast-bone, and is attached high up to the arm (pvc- 
toralis major). In some of the other Apes this second part of the biceps is attached to a bent 
projection (coracoid) of the blade-bone, so that it has no direct attachment with the chest itself. 
The Siamang can walk fairly in the erect posture by balancing with the arms, or by placing them 
over the head, and it has a great power of grasp with its toe-tliumb. The shape of the foot resembles 
that of man more than that of the Troglodytes and Orangs, and the heel-bone is strong, and projects but 
slightly, and the toe-tliumb is stout and long. The muscles of the foot arc, as it were, more separate 
than in man, especially the flexors : and there is an extra muscle, an abductor of the third joint of the 
second toe. 
The ability to walk well was proved when a tame Siamang used to walk along a cabin table at sea, 
without disturbing the crockery ; and curiously enough this was better done than were some of the 
ordinary movements of the hand, for drinking out of the palm was a most ineffective and clumsy effort. 
The bones of the foot resemble those of man more than do those of the Apes already noticed ; 
but the first and second fingers are united by a fold of skin. 
Under the jaw and along the throat of a tame Siamang, a large swelling, not very well covered 
with hair, was visible enough. This was a vast air or laryngeal pouch, and pressure emptied it into 
the throat. Hence the creature in this point resembles the Orangs and the Troglodytes, but the use 
of the sac could not be satisfactorily decided. The sac opens into the windpipe by two apertures, 
which are in a membrane that unites the base of the tongue and the organ of voice together. It has 
an uvula. 
They are quiet, inoffensive animals, full of affection for man, and having good memories. Their 
* The abductor of the third joint of the second finger. The thumb counts as the first finger. 
