Page:EB1911 - Volume 28.djvu/589

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WHALE
569

swimming through the water; the tail, however, is not placed vertically as in fishes, but horizontally, a position which accords better with the constant necessity for rising to the surface for the purpose of breathing. The hairy covering characteristic of all mammals, which if present might interfere with rapidity of movement through the water, is reduced to the merest rudiments—a few short bristles about the chin or upper lip—which are often only present in young animals. The function of keeping the body warm is performed by a thick layer of non-conducting material, the “blubber,” a dense kind of fat placed immediately beneath the skin. The fore-limbs, though functionally reduced to mere paddles, with no power of motion except at the shoulder joint, have beneath their smooth and continuous external covering all the bones, joints and even most of the muscles, nerves and arteries of the human arm and hand; and rudiments even of hind-legs are found buried deep in the interior of the animal, serving no useful purpose, but pointing a lesson to those able to read it.


Fig. 1.—The Greenland or Arctic Right Whale (Balaena mysticetus).

In the present article attention is directed only to what may be regarded as the typical whales. Of these the Greenland or Arctic right whale (Balaena mysticetus) attains, when full grown, a length of from 45 to 50 ft. In this species (fig. 1) all the peculiarities which distinguish the head and mouth of the whales from those of other mammals have attained their greatest development. The head is of enormous size, exceeding one-third the whole length of the creature. The cavity of the mouth is actually larger than that of the body, thorax and abdomen together. The upper jaw is very narrow, but greatly arched from before backwards, to increase the height of the cavity and allow for the great length of the whalebone-blades; the enormous lateral halves of the lower jaw are widely separated posteriorly, and have a further outward sweep before they meet at the symphysis in front, giving the floor of the mouth the shape of an immense spoon. The whalebone-blades attain the number of 380 or more on each side, and those in the middle of the series have a length of 10 or sometimes 12 ft. They are black in colour, fine and highly elastic in texture, and fray out at the inner edge and ends into long, delicate, soft, almost silky, but tough hairs. The remarkable development of the mouth and of the structures in connexion with it, which distinguishes the right whale from all its allies, is entirely in relation to the nature of its food. By this apparatus the creature is enabled to avail itself of the minute but highly nutritious crustaceans and pteropods which swarm in immense shoals in the seas it frequents. The large mouth enables it to take in at one time a sufficient quantity of water filled with these small organisms, and the length and delicate structure of the whalebone provide an efficient strainer or hair-sieve by which the water can be drained off. If the whalebone were rigid, and only as long as is the aperture between the upper and lower jaws when the mouth is shut, a space would be left beneath it when the jaws were separated, through which the water and the minute particles of food would escape. But instead of this the long, slender, brush-like, elastic ends of the whalebone blades fold back when the mouth is closed, the front ones passing below the hinder ones in a channel lying between the tongue and the lower jaw. When the mouth is opened, their elasticity causes them to straighten out like a bow unbent, so that at whatever distance the jaws are separated the strainer remains in perfect action, filling the whole of the interval. The mechanical perfection of the arrangement is completed by the great development of the lower lip, which rises stiffly above the jaw-bone and prevents the long, slender, flexible ends of the whalebone from being carried outwards by the rush of water from the mouth, when its cavity is being diminished by the closure of the jaws and raising of the tongue.

If, as appears highly probable, the “bowhead” of the Okhotsk Sea and Bering Strait belongs to this species, its range is circumpolar. Though found in the seas on both sides of Greenland, and passing freely from one to the other, it is never seen so far south as Cape Farewell; but on the Labrador coast, where a cold stream sets down from the north, its range is somewhat farther. In the Bering Sea, according to Scammon, “it is seldom seen south of the fifty-fifth parallel, which is about the farthest southern extent of the winter ice, while in the Sea of Okhotsk its southern limit is about the latitude of 54°.” “Everything tends to prove,” Scammon says, “that Balaena mysticetus is truly an ‘ice whale,’ for among the scattered floes, or about the borders of the ice-fields or barriers, is its home and feeding-ground. It is true that these animals are pursued in the open water during the summer months, but in no instance have we learned of their being captured south of where winter ice-fields are occasionally met with.” The occurrence of this species, therefore, on the British or any European coast is unlikely, as when alive and in health the southern limit of its range in the North Sea is from the east coast of Greenland at 64° N. lat. along the north of Iceland towards Spitzbergen, and a glance at a physical chart will show that there are no currents setting southwards which could bear a disabled animal or a floating carcase to the British shores. To this improbability may be added the fact that no authentic instance has been recorded of the capture or stranding of this species upon any European coast. Still, as two other Arctic cetaceans, the narwhal and the beluga, have in a few instances found their way to British shores, it would be rash to deny the possibility of the Greenland right whale doing the same.

The black whale or southern right whale (B. australis) resembles the preceding in the absence of a dorsal fin and of longitudinal furrows in the skin of the throat and chest, but differs in that it possesses a smaller head in proportion to its body, shorter whalebone, a different-shaped contour of the upper margin of the lower lip, and a greater number of vertebrae. This type inhabits the temperate seas of both southern and northern hemispheres and is divided into several species according to their geographical distribution: B. biscayensis of the North Atlantic, B. japonica of the North Pacific, B. australis of the South Atlantic, and B. antipodarum and B. novae-zelandiae of the South Pacific. But the differential characters by which they are separated are slight, and the number of specimens available for comparison is not sufficient to afford the necessary data to determine whether these characters can be regarded as specific or not.


Fig. 2.—The Black Whale or Southern Right Whale (B. australis).

The Biscay right whale was formerly abundant in the North Atlantic, but is now verging on extinction. This was the whale the pursuit of which gave occupation to a numerous population on the shores of the Basque provinces of France and Spain in the middle ages. From the 10th to the 16th centuries Bayonne, Biarritz, St Jean de Luz and San Sebastian, as well as numerous other towns on the north coast of Spain, were the centres of an active whale “fishery” which supplied Europe with oil and whalebone. In later times the whales were pursued as far as the coast of Newfoundland. They were, however, already getting scarce when the voyages undertaken towards the close of the 16th century for the discovery of the north-eastern route to China and India opened the seas round Spitzbergen; then for the first time the existence of the Greenland whale became known, and henceforth the energies of the European whale-fishers became concentrated upon that animal. Among instances of the occurrence of this whale in Europe in modern times