As to the skeleton of the limbs, here is a summary of what can be said about it from the point of view which specially concerns us now. In the thoracic limb the humerus presents an interesting peculiarity: the perforations of the olecranon cavity (which receives the extremity of the ulna) are very frequent in prehistoric bones in Europe (10 to 27 times in 100), as well as in America (31 times).[84]
This perforation is met with more often among men than women, perhaps because it is more especially connected with the extent and frequent repetition of the movements of flexion and extension. Here is its growing frequency in the races from a list which I have drawn up with series varying from 20 to 249 humeri: white population of the United States (3.8 times in a hundred), French, Fuegians, Ainus, Basques, Melanesians, Japanese, Negroes, Polynesians, Mongolians, and American Indians (36.2 times in a hundred). The torsion of the humerus—that is to say, the degree of rotation of the lower part of this bone in relation to its upper part, is a character of a certain seriate value; but it is of no use in the differentiation of races. Besides, the degree of torsion varies too much in the same race: it is greater in woman than in man, in short than in long humeri (Manouvrier, Martin, etc.). This torsion is measured by the angle of torsion, which is taken either according to Broca’s method or Gegenbaur’s. This is how the different peoples are arranged according to the decreasing figures of this angle (series of 10 humeri): according to Broca’s system:—Melanesians (angle of 141°), Guanches, Arabs or at least Kabyles, Polynesians, Negroes, Peruvians, Californians, Europeans, French (164°); according to Gegenbaur’s system:—Ainus (149.5°), Fuegians, Veddahs, Japanese, Swiss, Germans (168°). Until further discoveries are made, a single fact becomes prominent from the examination of this character—that is, that the torsion appears to be greater in white races than in black and yellow. In the ulna Collignon has noted a special incurvation in certain prehistoric bones.
FIG. 23.—A, Skull with Inca Bone, b;
B, Malar Bone divided in two (a, os Japonicum);
C, superior part of femur with third trochanter (3), and the hypo-trochanteric fossa (x);
1 and 2, normal trochanters.
In the femur one peculiarity has especially attracted the attention of anthropologists in recent times; it is the more or less frequent presence of the third trochanter (Fig. [23], C 3), or tuberosity situated between the great (ibid., 1) and the lesser (ibid., 2) trochanter on the offshoot from the linea aspera which furnishes a point of attachment to the lower part of the gluteus maximus. This projection, pointed out and studied for the first time by Houzé,[85] appears in infancy as a special centre of ossification analogous to those of the other diaphyses (Török, Deniker, Dixon), and so does not seem to depend on the greater or less development of the gluteus maximus (Bertaux).[86] The third trochanter is almost always accompanied by a hypotrochanteric fossa (Fig. [23], C).
Here is the frequency with which the third trochanter occurs according to a list which I have compiled:—
| Number of Femurs. | Populations. | Frequency per 100 of the 3rd trochanter. | Observers. | |
| 42 | Belgians and French of the Reindeer Period | 13 | Houzé | |
| 28 | Negroes | 21 | Houzé, Costa | |
| 68 | Ainus | 26.5 | } | Koganei |
| 73 | Japanese | 28.8 | ||
| 67 | Inhabitants of Brussels | 30.2 | Houzé | |
| 102 | Italians | 30.4 | Costa | |
| 54 | Hungarians | 36.1 | Török | |
| 110 | Belgians and French of the Polished Stone Period | 38 | Houzé | |
| 76 | Fuegians | 64.3 | Hyad., Denik., Martin, Costa | |
Two points will be observed in this table, the rarity of the third trochanter among Negroes, and its excessive frequency among the Fuegians. The women of the latter have also the hypochanteric fossa 80 times in a 100 (out of 76 femurs examined); it almost forms then, like the third trochanter, a character of race.