SEA LION.
(From the Living Specimen in the Zoological Gardens, London.)

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Much confusion for a long time reigned concerning the species of the Sea Lions. This difficulty has arisen from several reasons. Sealers have long distinguished the two kinds, namely, Fur Seals and Hair Seals; but among the thousands and thousands of skins annually brought home, little attention was paid to the animal from which the different skins were obtained, other than to its mere market value. While skins, and occasionally skulls or skeletons, found their way into our museums, seldom have these specimens been certified as belonging to one and the same individual; and in other cases they have been so mixed that identification has been little short of a riddle. Failing precision with regard to skins and skulls, the anatomists have been too prone to found genera and species on imperfect data, ignoring differences of sex, age, and the like, and thus many technical divisions have been introduced which we hardly think it worth while here rigidly to follow.

EAR OF OTARIA. (Natural size.)
After Murie.

The family Otariidæ, or Eared Seals, was distinguished, and so named by the French naturalist M. Péron early in this century, from the animals of this section possessing a small scroll-like external ear, an appendage wanting in the Seals generally. They moreover differ from the latter, and resemble the Walrus, inasmuch as they can freely progress on all-fours on land. Their skull is somewhat Bear-like, the neck being long. The fore-limbs, set well back, are tolerably free, and rest on a thin, broad, but flat hand of great size, encased in a leathery-like substance. The thumb is remarkably stout, and far exceeds the other fingers in length, and on all the merest indications of nails are present. Each finger is tipped with a long spatular cartilage, as are the toes of the hind feet, thus giving them great flexibility. The hind limbs are not so loosely attached by the tail membrane as in the Walrus, and the short tail is apparent close to the heels. The great toe is by far the longest and strongest, size diminishing from this to the little toe. As a rule, this family are nimbler on land than is the Walrus family, though both walk flat-footed in a somewhat similar fashion. The gait of the Otaries, however, from the slightly greater restraint of their closer-linked hind quarters and legs, and from the lengthening of their fore-flippers, is ridiculously peculiar. The fore-flippers, as Mr. Frank Buckland drolly observes, remind one of Bob Ridley’s shoes in a nigger performance. From the wrist they flop, flop, in a semicircle as right and left foot is alternately raised, while the hind quarters hitch, hitch, as each hind foot comes wobble, wobble, under the belly, the great toes even overlapping the fore-flipper. The Sea Lions have long, stout, exceedingly mobile whiskers, though these are by no means so profuse, thick-set, or strong as in the Walrus. Their skeletons differ from the latter in several particulars of minor importance, the chief distinctions being in the skull and dentition. There are on each side three incisors in the upper jaw, and two in the lower. The middle ones are smallest, the upper outer ones more often very large. The canines are still larger, and recurved; but though powerful, not to be compared with the great tusks of the Morse. There are more commonly five teeth of the molar series, of which the crowns are bluntly conical, and the roots simple. The milk-teeth are mostly shed before birth. The dental formula of the Otariidæ may be represented thus:—Incisors, 3–3 2–2; canines, 1–1 1–1; premolars, 4–4 4–4; molars, 2–2 1–1 = 36. The fore part of the skull is not so swollen out and abrupt as in the Walrus, the smaller size of the canines not requiring such space. In youth the skull is long, low, and flat, but in the old males there arise bony crests and processes, altering the shape, especially behind, so that recognition of the species is even difficult.

TEETH OF OTARIA. (After De Blainville.)

As the habits of the family of the Eared Seals are in the main very similar, and seeing how difficult it is from mere outward inspection to tell one species from the other, it seems advisable to follow Mr. J. W. Clark’s mode of treatment, and consider all under the single genus Otaria, though incidentally allusion will be made to such forms as are indicative of generic distinction.