The great distinction between the two animals is that the Nschiego’s forehead, formed by the frontal bone, rises up from the great brow ridge, and is visible from the front. This is not the case with the Gorilla, whose forehead recedes greatly. Both animals have the same number of ribs (thirteen), but those of the Nschiego are more man-shaped and are not so broad and close together; and their chests differ in breadth, for the breast-bone of the new Ape is narrower, but it is long and thick. The blade-bone, so important to the Gorilla, is equally so to the Nschiego, but it is longer and narrower on the back, and its spine is very oblique. Possibly this conformation of the bone may have to do with the constant climbing of the Bald-headed Ape, but nevertheless the spines on the neck-bones, which give origin to such exceedingly strong muscles in the Gorilla, are much smaller in the Nschiego. The first neck-bone, or atlas, has no spine in this Ape, in which it is like man, and the axis, or second, has a forked spine, and is crested at the end, but otherwise is like that in man. Finally, the rudiment of a tail is like that end of the back-bone found in the Gorilla and in man. These are the principal points and the most important distinctions; they show that the Nschiego cannot be of the same kind or species as the Gorilla, but is a Troglodyte, resembling the Gorilla somewhat in its skeleton, and although smaller than the male, still quite, if not more, man-shaped. The London Zoological Society own a fine example of the Bald-headed Chimpanzee (_Anthropopithecus calvus_), which, under the name of “Sally,” is known to every frequenter of their famous Gardens, where it has resided since October, 1883. THE KOOLO-KAMBA.[9] This kind of Troglodyte is celebrated for saying koola-koolo over and over again as its favourite cry, for having a very extraordinary frog-like figure, and for being one of those creatures which are exceedingly interesting to zoologists, because they are, as it were, half one thing and half another. A neighbour of the great Apes already noticed, it associates also with the common Chimpanzee, in the quiet forests of Western Equatorial Africa. In one of these Du Chaillu first saw it, and he describes his discovery as follows:--