162 READINGS IN EVOLUTION, GENETICS, AND EUGENICS 



On the other hand, Prof. Flower tells me that in his opinion it is but 

 an expression of impoverished nutrition during the growth of the bone. 

 ii. Flattening of Tibia. In some very ancient human skeletons 

 there has also been found a lateral flattening of the tibia, which rarely 

 occurs in any existing human beings, but which appears to have 

 been usual among the earliest races of mankind hitherto discovered. 

 According to Broca, the measurements of these fossil human tibiae 

 resemble those of apes. Moreover, the bone is bent and strongly 



GAPVCHII/ 



FIG. 34. Perforations of the humerus (supra-condyloid foramen) in three 

 species of Quadrumana where it normally occurs, and in man, where it does not 

 normally occur. Drawn from nature. (From Romanes.') 



convex forwards, while its angles are so rounded as to present the 

 nearly oval section seen in apes. It is in association with these 

 ape-like human tibiae that perforated humeri of man are found in 

 greatest abundance. 



On the other hand, however, there is reason to doubt whether 

 this form of tibia in man is really a survival from his quadrumanous 

 ancestry. For, as Boyd-Dawkins and Hartmann have pointed out, 

 the degree of flattening presented by some of these ancient human 

 bones is greater than that which occurs in any existing species of 

 anthropoid ape. Of course the possibility remains that the unknown 

 species of ape from which man descended may have had its tibia more 

 flattened than is now observable in any of the existing species. Never- 



