488 THE ANATOMY OF VERTEBRATED ANIMALS. 



c. The Anthropidoe are I'epresented hj the single genus 

 and species, Man, and they are distinguished from the 

 Simiadce, and especially the Anthropomorjpha, by the follow- 

 ing characters : 



In progression on the ground, the erect posture is the 

 easiest, and no assistance is given by the arms, which are 

 shorter than the legs. After Ijirth, the proportions of the 

 body alter in consequence of the legs growing faster than 

 the rest of the body. In consequence, the middle point of 

 the height of the body — which, at birth, is situated about the 

 umbilicus — becomes gradually lower, until, in the adult 

 male, it is as low as the symphysis pubis. 



In the manus, the poUex is strong and long, reaching to 

 the middle of the basal phalanx of the index digit. In the 

 pes, the tarsus takes up half the length of the foot ; the 

 calcaneal process is long, and expanded posteriorly. The 

 hallux has half the length of the foot, and is nearly as 

 long as the second digit ; and its mobility in adduction and 

 abduction is slight, compared with that of the hallux of 

 the other Primates. 



Hair is more abundant upon the crown of the head; 

 and, usually, in the axillae, the pubic region, and the front 

 pai't of the thorax, than elsewhere. 



In the new-born infant the whole dorso-lumbar region of 

 the spine is concave forwards, and the vertebro-sacral an- 

 gulation is slight ; but, in the adult, the spinal column is 

 concave forwards in the thoracic, and convex forwards in 

 the lumbar, region, mainly in consequence of the dispo- 

 sition of the elastic ligaments which connect the faces and 

 the arches of the vertebrse. There is a strongly-marked 

 vertebro-sacral angulation. Normally, there are twelve 

 dorsal, five lumbar, five sacral, and four coccygeal vertebrse, 

 and the transverse processes of the last lumbar vertebra 

 are not expanded or directly connected with the ilia ; but, 

 in these respects, variations occur. 



The spinous processes of the middle cervical vertebrae 

 are much shorter than the seventh, and are usually bifur- 

 cated. The breadth of the saci'um is gi'eater than its 



