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Show 76.] DR. J. VON HAAST ON A NEW ZIPHIOID WHALE. 11 The crowns of the teeth stand at about the same level with the central line of the palate. The opening along the upper surface of the rostrum is still unclosed, thus showing that the animal is not so aged as the next specimen, No. 2. * I may here add that the rostrum in all three skulls is half an inch shorter than the mandible, and that it lies in a well-defined groove in the latter. Skull No. 2.-The measurements of this skull, as far as I was able to obtain them, show that, as previously stated, it was not so elongate as the former, but somewhat broader and more massive in all its proportions. The rami of the mandible widen much sooner than those of the former; about 7 inches from their anterior extremity they expand considerably in order to form the alveolar cavity for a large tooth which here rises conspicuously on both sides, having a vertical position. This tooth has a compressed triangular shape, is 2f inches broad at its base on the line of the gums, and rises If inch above them. On the inner side near the top it is slightly abraded, and on the outside broken considerably, so as to suggest that the animal used it for the purpose of defence or attack. This injury has taken place on both teeth, so that they have lost their point and show a ragged horizontal apex with a width of nearly a quarter of an inch. From behind the tooth the rami expand very little as far as the gape. A similar row of small teeth, described as occurring in the first specimen, exists also in this second skull; but there are apparently only 17 of them. Their position is exactly the same as in the foregoing, the first standing exactly above the posterior edge of the base of the large tooth in the lower jaw. The teeth have the same form as those previously described, except that they are generally thicker; this becomes conspicuous with the 7th tooth, after which they gradually increase to the 13th, which is A of an inch thick at its base and stands 0*45 inch above the gums Ihey then keep nearly the same size to the posterior end of the series As the space on which these 17 teeth stand is only 4*25 inches long, besides their greater stoutness they are far more crowded than m the first-described skull. Owing to the fact that the gums have dried more thoroughly in this than in the two other skulls, in both of which the teeth stand erect with the curve of the apex directed inwards, the teeth in this skull are no longer in their normal position, but lie somewhat forwards on The groove in the upper surface of the rostrum, between the premaxillaries, is filled by a convex ridge of dense bone with a small channel on each side. That this is only caused by age, and that is neither a sexual nor a specific character, is proved by the fart that the next skull, No. 3, which is doubtless a young half-erown specimen of the same sex as the one under review, has this erooVe on the top of the rostrum still open, and thus resembles the skull N o 1 although in the latter that groove is narrower and more shallow ' ' Skull No. 3.-Assuming that the last-described skull belongs to |