OCR Text |
Show 10 DR. J. VON HAAST ON A NEW ZIPHIOID WHALE. [Jan. 4, Examining the skulls separately, we find that the one marked No. 1 is longer but narrower than No. 2. This is still more striking when we compare the two rostrums with each other, that of skull No. 1 being considerably narrower than that of skull No. 2. The same observation applies to the mandibles, which in No. 1 only widen very gradually and are much narrower all along than those of skull No. 2. In fact, if both skulls had been obtained separately I believe that they would probably have been assigned to two distinct species. a. Side view of upper and lower jaws, covered with the dried skin, of No. 2 (aged male?), showing the row of small teeth above and the single large mandibular tooth. From a photograph. b. Four of the upper teeth, with the whole of their roots exposed; natural size. When the skull No. 1 was first examined by me, the sharp point of a tooth in each ramus of the lower jaw, when passing the finger over the gums, was discernible; but I doubt if this was to be felt before the gums were dried up. In cutting a portion of the gums away, the apex of a very flat tooth, rather acutely triangular as far as visible, was exposed, which stands about one eighth of an inch above the upper surface of the ramus. This tooth is imbedded in a very narrow alveolar cavity situated near the posterior edge of the symphysis, the ramus here scarcely bulging out; this is still more obvious if we compare that portion of the ramus with that of skulls Nos. 2 & 3. Above the posterior edge of the small tooth in the lower jaw, and which without doubt has to perform some function, notwithstanding that it is covered by the gum, a row of small conical teeth, the apices slightly incurved, begins on each side of the upper jaw, reaching within an inch of the gape of the mouth, which, however, may have somewhat retreated by the drying of the skin. These small teeth are situated in a well-defined dental groove in the gums. There were 19 teeth on each side, of which, however, several are broken off. They are from 0*20 to 0*40 inch long, and occupied a line 6*12 inches in length, standing nearly the eighth of an inch apart. Of the whole series, the first or anterior tooth is the smallest, the succeeding ones gradually getting larger till the eighth, and then maintaining the same size to nearly their termination. |