The black dolphin (_Globicephalus globiceps_) is also an inhabitant of the Polar seas, both beyond Behring Strait, and between Greenland and Spitzbergen. It is, however, frequently met with in waters further south. Its length averages about twenty-four feet, and its circumference ten feet. Its smooth oily skin is bluish-black on the upper, and an obscure white on the lower, parts of the body. Twenty-two or twenty-four strong interlocking teeth in each jaw form its formidable apparatus of offence and defence; its dorsal fin is about fifteen inches high; its tail five feet broad; the pectoral fins are long and narrow, and well adapted to assist their owner in its rapid movements. It consorts with its kind in herds of several hundreds, under the guidance of some old and wary males, whom the rest follow as docilely as a flock of sheep their bell-wether; hence the Shetlanders term it the “ca’ing whale.” Large shoals are frequently stranded on the shores of Norway, Iceland, and the Orkney, Faroe, and Shetland Isles, furnishing the inhabitants with a welcome booty. * * * * * To the same latitudes belong the ferocious orc or grampus (_Delphinus orca_), the tiger of the seas, which not only attacks the porpoise and dolphin, but even the colossal whale. Its broad deep body is black above and white beneath; the sides are marbled with black and white. There are thirty teeth in each jaw, those in front being blunt, round, and slender, while those behind are sharp and thick; and between each is a space fitted to receive those of the opposite jaw when the mouth is closed. The back fin of the grampus is of great size; sometimes measuring as much as six feet in length, from the base to the tip. The grampus generally voyages in small squadrons of four or five individuals, following each other in single file, and alternately rising and sinking in such a manner as to resemble the undulatory motions of a huge kraken or sea-serpent. * * * * * Among the inhabitants of the Polar Ocean must certainly be included the Polar bear (_Thalassarctos maritimus_), since it swims and dives with great dexterity, and, moreover, is often found on the drifting ice-floes at a distance of eighty to one hundred miles from land. It is a creature of great strength, great fierceness, and great courage, though we may not accept the exaggerated accounts of it which enliven the narratives of the earlier voyagers. [Illustration: POLAR BEARS.]