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orang, commencing from the vertebral column, are as follows : 

 The vertebral column describes only one curve, inclining forward, 

 where it supports the head with its large jaws and teeth. The 

 vertebrae in the neck, seven in number as usual in the mammalia, 

 are chiefly remarkable for the great length of the simple spinous 

 processes developed more than in most of the inferior apes, in 

 relation to the necessities of the muscular masses that are to sus- 

 tain and balance the head that preponderates so much forward on 

 the neck. The vertebrae maintain a much closer correspondence 

 in size, from the cervical to the dorsal and lumbar region, than in 

 the human skeleton. With regard to the dorsal vertebrae, or those 

 to which moveable ribs are articulated, there are twelve pairs in the 

 orang; seven of them send cartilages to join the sternum, which is 

 more like the sternum in man than in any of the inferior quadru- 

 mana : it is shorter and broader. In the smaller long-armed apes 

 (Hylobates\ which make the first step in the transition from the 

 ordinary quadrumana to the man -like apes, the sternum is remark- 

 ably broad and short. The lumbar vertebrae are, originally, five 

 in number in the orang ; but one or two may coalesce with the 

 sacrum. The sacrum is broader than in the lower quadrumana, 

 but it is still narrow in comparison with its proportions in man. 

 The pelvis is longer. The iliac bones are more expanded than 

 in the lower quadrumana, but on the same plane, and are flat- 

 tened and long. The tuberosities of the ischia are remarkably 

 developed, and project outward. All these conditions of the ver- 

 tebral column indicate an animal capable only of a semi-erect 

 position, and present a modification of the trunk much better 

 adapted for a creature destined for a life in trees, than one that is 

 to walk habitually erect upon the surface of the ground. But 

 that adaptation of the skeleton is still more strikingly shown in 

 the unusual development of the upper prehensile extremities. The 

 scapula is broad, with a well-developed spine and acromion ; there 

 is a complete clavicle ; the bone of the arm (humeru's) is of remark- 

 able length, in proportion to the trunk; the radius and the ulna 

 are also very long, and unusually diverging, to give increased sur- 

 face of attachment to muscles; the hand is remarkable for the 

 length of the metacarpus, and of the phalanges, which are slightly 

 bent towards the palm; the thumb is less developed than the cor- 

 responding digit in the foot; the whole hand is admirably adapted 

 for retaining a firm grasp of the boughs of trees. In the structure 

 of the carpus, there is a well-marked difference from the human 



