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Show 1876.] A Y O U N G D E L P H I N U S ALBIROSTRIS. 681 passing from the angle of the mouth to the root of the flipper, separated this patch from the white of the throat. The second white patch was much smaller in its area (7 in. by 2\ in.) and not so bright in colour. It was placed at a higher level than the first, and behind it. The third patch was very large (14 in. by 4 in.), and oblong or elliptical in shape. It was placed behind the middle vertical line, and was uniform over its greater part; but as the black shaded into the white, the uniformity of the latter was broken by numerous black or dark grey streaks. It was separated from the white of the belly by a narrow but decided slate-coloured band. Head.-The curve from the neck was uniform, but at the same time decided ; and this gave the head a massive appearance. The jaws were wedge-shaped; and the lower lip projected half an inch further forwards than the upper. Traversing the white snout was a well-marked furrow or groove, which commenced at the oral fissure close to the angle of the mouth, and passed round the snout to a corresponding point on the opposite side. Its depth was greater laterally than in front; and it served to give the animal a peculiar beaked appearance. From each side of the white snout, about 1 inch above the fissure of the mouth and immediately below the furrow, four strong black bristles projected. They were placed in a straight line and were a \ of an inch apart from each other. The blow-hole was situated almost in a straight line above the eye. It had the ordinary semilunar form, and was 1 inch in breadth. The eye was protected by well marked eyelids, the fissure between which was about \ inch long. Surrounding the eye the integument had a deeper black tint ; and about an inch from it, it was surrounded by a faintly marked circle or ridge., The auditory aperture could not be detected. Dentition.-In the upper jaw there were twenty-four teeth upon each side. Those in the centre of the range were the largest, and the anterior were smaller than the posterior. They commenced about \ of an inch from the middle line; and the first three on each side were not visible above the mucous membrane of the gum, but could be readily felt. Those of the lower jaw were twenty-six in number on each side. The first tooth was placed about ~ an inch behind the middle line, and, with the succeeding three, was completely covered by mucous membrane. When the mouth was closed the teeth of the two jaws interlocked ; but the two anterior teeth of the lower jaw had no opposing teeth in the upper jaw. They were conical in shape, sharp and curved, the concavity being towards the tongue. They were freely movable, the greatest range of movement being outwards. General contour of body. -This is well seen in the accompanying figure (Plate LXIV. fig. 1); and it will be noticed that, instead of tapering uniformly from behind the dorsal fin to the tail, the body suddenly expands in a vertical direction and then narrows into the part from which the tail springs. This gives a sort of humped appearance to this portion of the animal; and the hump suggests the idea of a rudimentary dorsal fin. That it is so in reality is rendered |
