108 
THE VOYAGE OF H.M.S. CHALLENGER 
83 in a male Illinois, 81 in a male Puelclie Indian, 84 in an ancient Peruvian; and 
M. Topinard has given 84*1 as the mean index of five South American men, and 83 '1 as 
that of six South American women. The mean tibio-femoral index in the Yahgan 
Fuegians measured by Dv, Garson was 847. 
A comparison of the several indices, computed from the measurements of the 
skeletons of the various races now examined, shows that considerable diversity exists 
in the proportionate length of the tibia and femur, so that in some the leg api3roaches 
nearer to the length of the thigh than in others. In attemptiug, however, to form an 
estimate of the disparity which exists between different races, one is met, not only with 
the difficulty which one experienced in comparing the proportionate lengths of the forearm 
and upper arm, viz. , the small number of specimens of some of the races that have as 
yet been measured, but with the difierent methods of measurement which have been 
employed by anatomists, so that they cannot at all times be compared with each other. 
Hence, I do not feel prepared with the requisite data to make even such a preliminary 
grouping of these races, based on the proportional length of the leg and thigh, as I 
ventured to do, though with much diffidence, in the section on the superior extremity. 
As it is obvious, however, that in some races the leg is longer in proportion to the thigh 
than in other races, some people may be called long-legged dolichoknemic {Kvrjfxr}, tibia), 
others short-legged, hrachyknemic ; the word leg being used in its strict anatomical sense 
to express that segment of the lower limb which lies between the knee and ankle 
joints. 
If we assume a tibio-femoral index, 83, as marking the division between the 
proportionally long-legged and short-legged, then we. may say that those races, in which 
the mean index is 83 or upwards, are dolichoknemic, and amongst these we might rank 
the Australians, Tasmanians, Negros, Andaman Islanders, Negritos, American Indians, and 
Yahgan Fuegians ; possibly also the Melanesians, though their exact position, as well as 
that of the Polynesians and Malays, is doubtful. On the other hand, when the mean 
tibio-femoral index is below 83, the race may be said to be brachyknemic, and in this 
group we might place Europeans, Chinese, Tartars, Lapps, Esquimaux, Samoyeds, possibly 
the other tribes occupying the most northern part of the continent of Asia, and the 
Mongolian race generally. 
In the next instance I shall proceed to the comparison of the extreme lengths of the 
humerus and radius with those of the femur and tibia in the same skeleton, a line of 
investigation which was introduced a number of years ago by M. Broca.^ If we assume 
the extreme length of femur -)- tibia (spine omitted) to = 100, then an intermemhi'ol index 
humerus -h radius x 100 
may be computed as follows : — 
femur -f tibia 
^ Sur les proportions relatives des membres supdrieurs et des membres inferieurs cliez les Negres et les Europeens, 
&c., Bull, de la Soc. d'Anthropologie, ser. 2, t. ii. p. 641, November 21, 1867. 
