THE EANGE OF VARIATION IN ANTHEOPID^. 495 



and Austi-alians, the fore arm and hand, and the foot and leg, 

 are often longer in proportion than in Europeans. From not 

 wearing shoes, the hallux is much more moveable in these 

 races, and the foot is commonly emjjloyed for prehension. 



There is no proof of what is so commonly asserted, that 

 the heel is longer, in proportion to the foot, in Negroes. 



The spines of the middle cervical vertebrae sometimes 

 cease, more or less completely, to be bifurcated in the lower 

 races. Thirteen pair of ribs are sometimes present, and 

 occasionally there is a sixth kimbar vertebra. There may be 

 one more sacral vertebra than the normal number ; and a 

 modification of the last lumbar, so that it resembles a 

 sacral vertebra, and becomes connected with the ilia, seems 

 to be more common in Australians and Bushmen than 

 in other stocks. 



In the lower races, the male pelvis is less in many of its 

 dimensions, and seems to differ more from the female, 

 especially in the tendency to equality of the transverse and 

 antero-posterior diameters of the brim, and the narrowness 

 of the intersciatic diameter, than in the higher races. This is 

 particularly obvious among the Australians. The antero- 

 posterior diameter of the brim of the pelvis is occasionally 

 greater than the transverse, and this variety would seem 

 to be commoner among the Bvishwomen of South Africa 

 than elsewhere. 



But it is in the skull that the different races of mankind 

 present the most striking osteological differences. The 

 proportions of the antero-posterior and the transverse 

 dimensions of the brain-case vary extremely. Taking 

 the antero-posterior diameter as 100, the transverse dia- 

 meter varies from 98, or 99, to 62. The number which thus 

 expresses the proportion of the transverse to the longitu- 

 dinal diameter of the brain-case is called the eeplialic index. 

 Those people who possess crania with a cephalic index of 

 80 and above are called hrachycephali ; those with a lower 

 index are doUclwcepliali. The brain-case also varies greatly 

 in its relative height. The proportion of the length of the 

 cerebral chamber to the basicranial axis (as 100) may rise 



