An Account Of The Beaked Whales Of The Family Ziphidoe In The Collection Of The United States National Museum PDF Download

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1910 edition. Excerpt: ...A very small circular opening at the base of the root marks the orifice of the nerve. The upper half of the teeth is smooth, and the tips slightly worn and fractured. The small elliptical worn area is situated on the convex side of the tooth, which appears to be the outer side. As the alveoli of the jaw are, however, filled with a network of bone, the teeth can not be inserted in them. They were detached when received. (Pl. 38, figs. 10, 11; pi. 22, fig. 2; pi. 23, figs. 2, 3.) Besides the difference in the size and form of the teeth in the two sexes, it is probable, as will be seen by consulting the foregoing data, that in the female the apex of the teeth does not extend more than a very small distance above the alveoli even in mature individuals, and probably often not more than a few millimeters; while in adult males the teeth are almost entirely protruded from the alveoli, which are filled with a coarse bony network. These differences are carried out in all the American specimens, and also characterized the New Zealand specimens, as may be learned from the accounts of Haast and Hector. A number of rudimentary teeth in addition to the large terminal pair have been noted in the Aresquiers, Buenos Ayres, and perhaps other specimens, and two such teeth were found in the mandible of the Barnegat specimen, behind the large pair. One of these rudimentary teeth has been preserved. It is cylindrical and moderately curved. The length is 16 mm. and the diameter 2 mm. The whole tooth, with the exception of the extreme tip, is thickly coated with cement. The root is closed and the crown acute and apparently abraded by use. (Pl. 38, fig. 5.) Returning now to the question of the validity of grebnitzkii as a species, I would say that after comparing...