The anatomy of the male Sanid is in some respects as peculiar as that of the female. The penis, when not erect, maintains an almost horizontal position (Fig. 55A, Bushmen). This feature is scarcely ever omitted in the rock art of the Bushmen, in their stylized representations of their own people. The prepuce is very long: it covers the glans completely and projects forwards to a point. The scrotum is drawn up close to the root of the penis, giving the appearance that only one testis has descended, and that incompletely (cf. Fig. 55A, second figure from right). These characters are clearly paedomorphous, and they are less marked in old men.

The Nilotids occupy the region of the upper Nile (Fig. 58). They are a homogeneous taxon, and can readily be described by noting their differences from the Sudanids. They are tall and slim, with very long limbs (Fig. 60A, p. 332, a Nilotid, Nuer tribe, showing a stance often adopted by members of this subrace). It is characteristic of the Negrids in general that the forearm is long, but this feature is emphasized in the Nilotids. The lower leg is thin and (as in most Negrids) almost devoid of a ‘calf.’ The Negrid tendency towards a projecting heel is pronounced in this subrace.

The penis is very long and rather thick when not erect, but this may perhaps be a general character of Negrids. From observations made while dissecting Negroes, the French anthropologist Paul Topinard confirmed the impression that this organ, in its flaccid state, was longer than that of Europeans, but he gave no indication of the subrace to which the corpses belonged. That Negrids have large penes is sometimes questioned, but those who doubt it are likely to change their minds if they will look at photographs nos. 8, 9, 20, 23, 29, and 37 in Bernatzik’s excellently illustrated book, Zwischen weissem Nil und Belgisch-Kongo. These represent naked male Nilotids, and appear convincing.

Ludwig Wolf, who made a study of the physical anthropology of the Baluba tribe, remarks that ‘As a general rule the male organ in its relaxed state is astonishingly strongly developed;’ but he was informed by Negresses who had cohabited with both Negrids and Europids that, when erect, the organ is of about the same size in the two races. Topinard had claimed that though the penis of Europeans was smaller than that of Negrids when flaccid, it was larger than theirs when erect.