On the other hand, several varieties of Negroes properly so-called wear but a fuliginous or reddish-brown tint. It is, therefore, by less superficial peculiarities that we distinguish the true Negro. His skull is elongated, and laterally compressed. Sometimes his jaw projects, a characteristic scientifically designated by the name of prognathism; sometimes it is more vertically disposed, but then the cheek-bones (or "zygomathic arches") are extremely prominent. His teeth project; that is, they are inclined outward, and always long and white. The skeleton, whiter than our own, is also heavier and more massive. The abdomen is exceedingly narrow, and with a conical cavity; the legs are bowed. Short the neck, broad the thorax, and convex, and generally well made. The muscles, but slightly developed in proportion to the dimensions of the osseous framework, have not the vivid red colour which distinguishes the flesh of the European; the blood is black, thick, and circulates slowly. The body is always deprived of hair; there is little or no beard; the hair of the head is black, woolly, and frizzled. The eyes are of the deepest black, but inexpressive. The forehead is low, the chin short, the mouth large, the lips are long and thick. Finally, and this is the most remarkable sign of the Negro's inferiority, the type of the face, in the same race, is so uniform that it is difficult to distinguish one individual from another. To this physical uniformity corresponds a moral and intellectual uniformity, which effaces, so to speak, all individuality. In Africa we meet with numerous tribes more or less intelligent and capable of being educated, many sanguinary and fierce, others benevolent and inoffensive; but the character and dispositions of a tribe are reproduced among all the individuals who compose it with scarcely perceptible differences. The Negroes of Africa may be divided into three principal varieties: the pure Negroes, the Kaffirs, and the Hottentots. The former comprehends all the populations of the east, centre, and west of Africa. Its primitive stock is supposed to be the people called Mandinké or Malinké (Mandingue), formerly established at Mendé, in the delta of the Nile, but who emigrated towards the western coast, and now inhabit the mountainous countries bordering on the Upper Senegal. Between this river and the Niger are grouped some tribes in whom the Berber or Semitic blood appears mingled with the Negro blood; such are the Yolofs, the Foulahs, and the Peulas, or Fellatahs. The latter are of a sooty black, with a well-shaped head, a square frontal development, thick and woolly hair. They have founded powerful states, and are considered as the true civilizers of the Soudan, where they have introduced Islamism.