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Show 158 PROF. W. H. FLOWER ON THE ELEPHANT SEAL. [Jan. 4, gone its greatest degradation, a few more stages of which would leave the animal little better provided with these organs than are the Ziphioid Cetaceans. The form of the brain-cavity of the Elephant Seal, as shown by the casts in the Museum of the College of Surgeons, is remarkable for its great width posteriorly compared with its length, and presents the greatest contrast, among the Seals, to that of Otaria, which differs but little from that of the terrestrial Carnivora. The short, globular form of the brain, as well as the numerous and closely packed convolutions of the surface of the hemispheres, is one of the many characters by which the Seals resemble the Cetacea. There is much in the general appearance of the skull of the Elephant Seal, especially the fore part, with its short nasal bones, broad depressed muzzle, wide flat palate, and simple, conical, recurved teeth, which presents some resemblance to the Carnivorous members of that group, such as Orca ; and it is singular, if only as a coincidence, that Mr. Mansel's large specimen shows a want of symmetry in the form of the anterior nares, the ossified septum being bent to the right, which recalls one of the peculiarities which distinguish the skull of most of the toothed Whales1. In the small development of the coronoid process of the lower jaw the Elephant Seal surpasses any of the Phocine series, and is furthest removed from the land Carnivores. As far as can be gathered from the narratives of those who have had the opportunity of observing this animal alive, its habits confirm the views derived from its structure. It appears to be more helpless on land and more active in the water than the other members of the group2. All the characters hitherto mentioned have been only modifications or exaggerations of those met with in other Seals, and are shared by some one or other of the group. There is one remarkable evidence of specialization which it possesses in common only (with modifications in detail) with its near ally Cystophora cristata-the dilatable sac connected with the nasal passages, developed (like so many of the singular pouches accessory to the respiratory organs) only in adult males. As I have had occasion to mention many structural points in which the Elephant Seal appears to approach nearer than other members of the group to the Cetacea, I must guard myself against being supposed to infer that it is genealogically in any way a connecting- link between the two. The Seals appear to me so distinctly an offshoot of the terrestrial Carnivora, that any consanguinity between them and the Cetacea must be excessively remote; and if the Elephant Seal is the most modified and specialized of the group, and i Prof. Huxley points out several characters in which the Seal's skull is "strikingly Cetacean " (' Manual of Anatomy of Vertebrated Animals,' 1871, p 425). 2 See Peron, 'Voyage de decouverte aux Terres Australes,' 1816, tome ii. p. 45 ; also Scammon, ' The Marine Mammals of the North-west Coast of North America' (1874), p. 117; Weddell, 'A Voyage towards the South Pole' (1825), p. 136. This is also the opinion of Mr. Moseley, one of the most capable and observing of naturalists who have come into contact with Sea Elephants in their native haunts. |