ANATOMICAL STRUCTURE OF ANTHROPOID APES. 88 



species {Hylolates sijndactylus, H. leueiseus, H. varla- 

 gatus, and H. concolor) there are thirteen dorsal, five 

 lumbar, six sacral, and four coccygeal vertebra3. 

 Cuvier counted in the siamaug, thirteen dorsal, five 

 lumbar, four sacral, and three coccygeal vertebrae. 

 In Hylohates agilis I counted thirteen dorsal, six 

 lumbar, five sacral, and four coccygeal vertebra?. 

 Hylohates syndactylus has long coccygeal bones, and 

 an elongated os sacrum, which gives the impression 

 of serving for the application of a short tail, or, 

 indeed, of being in itself a rudimentary tail. In 

 other respects the cervical, dorsal, and lumbar 

 vertebra} differ little in structure from those of man. 

 The ribs on the sternum, which widens abruptly 

 outwards, are strongly arched. The lowest of these 

 project, owing to the width of the shaft. In the 

 sternum there is a want of proportion between the 

 smallness of its body and the size and width of its 

 extremity. The ensiform appendix of this bone 

 is long and wide, and spatula-shaped at its lower 

 extremity. In the shoulder-girdle the clavicles are 

 very slender, and much arched. The scapulae, 

 on the other hand, are high and narrow, spatula- 

 shaped, and provided with a steeply projecting 

 acromion process, a strongly developed coracoid 

 process, and deep glenoid cavities. The upper 

 limbs are, in conformity with the general structure 

 of these apes, very slender ; the shafts of the bones 

 of the upper and forearm are elongated, with small 

 extremities. The condyles are small, especially 

 those of the elbow. The bones of the wrist, the 

 metacarpus, and the fingers are also long and slender. 



