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Show 1881.] PROF. W. H. FLOWER ON THE ELEPHANT SEAL. 149 exaggerate the size of every thing large had not had its influence this case, as it undoubtedly has with Cetaceans, Sirenians, and other marine " monsters." Skeletons are far more valuable than skins or stuffed specimens for giving dimensions, as the latter are susceptible of considerable factitious enlargement. Unfortunately there is not, as far as I can learn, any skeleton of a perfectly adult male Elephant Seal in any museum in Europe. The largest appears to be that at Berlin, of which I have given the size of the skull above, and of which the stuffed skin, according to Mr. J. W . Clark l, measures 14 feet 6 inches in length from tip of nose to tip of tail, and 16 feet 3| inches to the extremity of the hind flippers, taking the measurement along the curve of the back. Dr. Peters gives the length of the vertebral column of this specimen as 3700 millims.2, which, added to the length of the skull (490 millims.), gives 4190 millims., or 13 feet 9 inches for the whole length. Whether allowance has been made for the intervertebral spaces or not I do not know. Mr. J. A. Allen gives the length of the skeleton (nose to tail), allowing for the probable length of the intervertebral cartilages, of a male, said to be adult, from Heard Island, in the Museum of Comparative Zoology at Cambridge, Mass., as 4340 millims., or 14 feet 3 inches 3. The skull of this specimen is 480 millims. long. Skeletons of very young animals, between four five feet in length, are common in museums. Dentition.-Leaving out of consideration the exceedingly aberrant and specialized Walrus, the teeth of the Elephant Seal are more reduced in number, size, and form than those of any of the Pinnipedia, the only other member of the group which agrees with it in most of these characteristics being the closely allied Cystophora of the northern seas. The dentition when complete is i. \, c. \, pm. ^, m. \, though it frequently happens that one or more of the true molars, especially those of the upper jaw, are rudimentary or wanting. All the teeth, even the canines, are remarkable for their comparatively small enamel-covered crowns, and for the large size of their simple roots, which continue to grow in width as well as length during the adolescence of the animal, and are further enlarged in thickness by the addition of a considerable layer of cementum to their outer surface. In this character the teeth resemble those of many of the Odonto-cetes, so much so that in the case of isolated fossil teeth of the Crag formation it is often very difficult, if not impossible, to say whether they belong to Cetaceans or to Seals. Although other Pinnipeds show this peculiarity, it is carried to its greatest extent in the Elephant Seal. The very small size of all the teeth except the canines, and more especially those of the molar series, in proportion to the great magnitude of the animal, is very striking. They must, in fact, be almost functionless. 1 Nature, Sept. 2, 1875, p. 366. 2 Monatsb. der k. p. Akad. der Wissenschaft. zu Berlin, 1875, p. 393, footnote. 3 Op. cit. p. 749. |