This whale seldom exceeds fifty to sixty feet in length, or thirty to forty in girth, and, therefore, is by no means the head of its family. As in other species, the body is thick and bulky forwards, largest about the middle, and tapers suddenly towards the tail. The head is colossal; broad, flat, and rounded beneath, and narrow above; it forms about a third of the animal’s entire length, and is about ten or twelve feet broad. Its lips--such lips!--are five or six feet thick. They do not cover any teeth, but they protect a pair of very formidable jaws. The cavernous interior of the mouth is filled up with two series of whalebone laminæ, about three hundred in each, which require particular description. The whalebone, or baleen, as it is called, consists of numerous parallel plates, layers, or laminæ, each of which is formed of a central coarse fibrous layer lying between two that are compact and externally polished. But this outer part does not completely cover the inner; a kind of edge is exposed, and this edge terminates in a loose fringed or fibrous extremity. Moreover, at the base of each plate of baleen lies a conical cavity, covering a pulp which corresponds with it; and this pulp is sunk within the substance of the gum or buccal membrane stretched over the palate and upper jaw. The compact _outer_ layers of the baleen plate are continuous with a white horny layer of the gum, which passes on to the surface of each plate; and the pulp may be regarded, therefore, as the secreting organ of the internal coarse structure only. The filaments of the fringe are exceedingly numerous, and so fill up the mouth-cavity as to form a very efficient and ingenious sieve or strainer; and as the esophagus, or “swallow,” of the whale is so confined as to be unable to admit of the passage even of the smaller fish, and the food of the whale consequently is limited to minute organisms, such as the medusæ, this skilfully devised construction is absolutely requisite in order to retain the whole of those which are taken into the mouth. The mode in which the whale feeds may be thus described:-- The broad waters of the Arctic seas teem with innumerable shoals of molluscous, radiate, and crustaceous animals, and these are frequently so numerous as absolutely to colour the wave-surface. When a whale, therefore, desires food, it opens its colossal mouth, and a host of these organisms is, as it were, swept up by the great expanse of the lower jaw: as the mouth closes, the water is ejected, and the life it contained is imprisoned by the appliance we have attempted to describe. If we consider the number of whales found in the Northern seas, and the mighty bulk of each individual, our imagination entirely fails to appreciate the countless myriads of minute organisms which must be sacrificed to their due nourishment.