18 Proceedings of the Royal Physical Society. 



as expressed in Anthropometry by the hicmero-radial index^ 

 provide us with another race- character indicating a definite 

 evolution from the lower to the higher forms. 



In its normal state the carpus of man no longer presents 

 more than eight bones, for the os centrale of apes is an 

 exceedingly rare occurrence in man, although nearly all the 

 normal carpal bones have been found represented by two 

 portions. 



Turning to the bones of the lower limb, we find numerous 

 evidences of evolution. In the femur, its head shows clearly, 

 from the disposition of its articular surface, the nature of the 

 prevalent attitude and the amount of permanent erectness 

 attained in the attitude of the individual. 



The powerful ligamentum teres, whose absence is not 

 associated with any special loss of usefulness in the lower 

 limb, is regarded as the rudimentary remnant of the ambiens 

 muscle of birds. 



Upon the shaft, various characters express both rudi- 

 mentary as well as progressive forms of evolution. Thus 

 the occasional appearance of a third trochanter in connec- 

 tion with the gluteal ridge repeats a condition which is a 

 constant feature of the femur of certain mammals. The 

 posterior crest — the linea aspera — is an instance of progres- 

 sive evolution. The ridge so named is quite a human 

 characteristic, which apparently results from the action of 

 the two vasti muscles in association with their action in the 

 erect attitude. This narrow linea aspera is in reality a 

 narrow surface for which the French term "pilastre" is pre- 

 ferable. As a surface, it appears upon all mammalian 

 femora, but not until we reach man does this surface be- 

 come a narrow projecting crest, suggesting its name of linea 

 aspera. 



The now classic Trinil femur presented a condition of the 

 femoral shaft below the linea aspera, i.e., in its popliteal 

 region, which is only very rarely seen in man, and then only 

 in association with the femora of the lower races. In this 

 region, which is bounded laterally by the downward exten- 

 sion of the lips of the linea aspera, so as to include between 

 them nearly the entire width of the shaft, the surface so 



