eight to twenty, or even more, stiff, scattered hairs, after the manner of eyebrows; and eyelashes are likewise present. In most cases the hair of the true chimpanzee is of a black colour. Short whitish hairs may be observed on the lower part of the face and chin, as well as round the posteriors. Sometimes the colour of the hair is shot throughout with reddish or brownish black. The orang-utan, the chief representative of the anthropoids in Asia, differs from the African forms of this group, almost at the first glance, in the height of his skull, of which the fore-part is compressed and shortened in a backward direction. In the aged male it is, however, provided with high and erect bony crests, which give a prognathous appearance to the countenance. We take an aged male as the type of our description. The forehead is high and erect, not retreating like that of the chimpanzee; it is open, and has moderately convex frontal eminences. From the centre of the forehead a round or bluntly oval eminence sometimes projects. The supra-orbital ridges are strongly arched, yet not so prominent as that of the aged male chimpanzee, setting aside that of the gorilla. The eyes are not widely opened, nor are their lids large and furrowed, but on the lower lids there are deep wrinkles. The small bridge of the nose is generally much depressed, but sometimes assumes a slightly conical form as it issues from the central longitudinal depression of the face. The end of the nose, further removed from the eyes than is generally the case in the chimpanzee, is not so broad as it is in the latter animal and in the gorilla. The wings of the nose are narrow and highly arched in their upper part, divided from each other by a vertical furrow, and the nostrils are small and oval, separated by a thin partition. The upper lip is high, broad, and projecting, and seldom much wrinkled. It is divided from the cheeks and from the upper part of the face by a deep depression; and behind the cheeks two large and long-shaped or sometimes triangular pads of fat often project forwards and downwards. [Illustration: Fig. 7.--Head and shoulders of an aged male orang-utan.] The very mobile lips are furrowed, and not remarkably thick. The chin is very retreating, but somewhat uniformly rounded in front (Fig. 7). The small ear averages 55 mm. in length, and 12 mm. in width, and has a general resemblance in structure to the human ear (Fig. 8). On the fore-part of the short, thick neck there are irregular, and in some places very deep circular folds of skin. The throat-pouch distends part of this slack, wrinkled skin, which hangs down in front like a great empty wallet (see Figs. 7 and 9). [Illustration: Fig. 8.--Ear of the orang-utan.]