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Show 160 PROF. W. H. FLOWER ON THE ELEPHANT SEAL. [Jan. 4, same genus, especially as each subdivision contains but a single well-marked species; but as the separation has now been so generally adopted, and the name Macrorhinus has become so deeply rooted in zoological literature, perhaps more inconvenience would result from an attempt to reunite them than to retain them as distinct genera, and we may be content to show their close affinities by their union in one subfamily, Cystophorina?. The Elephant Seal has been known in zoological literature by three specific names, viz.:-leonina, Linn., founded on the so-called " Sea-Lyon " of Juan Fernandez, described and figured in Anson's Voyage, 1748, and undoubtedly the species under consideration ; elephantina, Molina, 1782, revived by Gray ; and proboscidea, Peron, 1815. The former, though, perhaps, the least appropriate, is clearly the first in point of time ; and as in using it we are not resuscitating a name that has become obsolete, or been entirely superseded by another that has met with general acceptance, it may be adopted with equal respect to the laws of priority and convenience; in fact all recent zoological literature shows that this name is gaining ground over both the others which have been proposed as substitutes. Unity or Plurality of Species.-The Elephant Seals which inhabit the Pacific coast of North America, formerly abundant, but now extremely reduced in numbers by the persecutions of the sealers, are supposed by Theodore Gill to be specifically distinct from those of the southern hemisphere, and have received the name of Macrorhinus angustirostris1. In J. A. Allen's valuable and exhaustive monograph on the North- American Pinnipeds this distinction is adopted ; but although the author speaks of the two species as presumably distinct, he says that, " so far as can be determined by descriptions, the Northern and Southern Sea-elephants differ very little in size, colour, or other external features." From evidence not very satisfactory, he supposes the southern species to be on the whole somewhat the larger of the two. The osteological characters upon which Gill bases his distinction are derived from the comparison of the skull of a probably full-grown female Californian Seal with the figure given by Gray in the ' Zoology of the Erebus and Terror,' of a two-thirds grown male (the one now in the British Museum) from the South Seas. This is incorrectly described by Gray as an "adult female;" and Gill has accepted this determination without question, although the characters of the skull, as seen in the drawing, the unworn condition and size of the canines, and open state of the sutures are sufficient to throw much doubt upon it. Unfortunately there is no skull of an adult female Sea-elephant in this country available for comparison; but from what may be inferred from other species of Seals, and from the evidence afforded by young specimens, it may be considered almost certain that the very character on which Gill has chiefly relied for specific distinction is a sexual one. The comparative narrowness of the muzzle is associated with the smaller deve- 1 Proc. Essex Inst. v. 1866, p. 13; Proc. Chicago Acad. Sci. i. 1866, p. 33. |