The whales, indeed, with their great jaws, in which, in a leisurely way, they enclose hosts of creatures so widely distributed, yet at the same time so minute, that they make, as it were, a part of the water, in which they are often only distinguishable by the colour their numbers impart to it, may be said to browse the sea, as oxen and horses browse the fields. Yet these poor, peaceful giants are persecuted, as we have seen, by packs of ravenous creatures against whom their very size makes them almost defenceless. As for the toothed whales, some of them—as, for instance, the killer or grampus—are amongst the most voracious of the dwellers of the sea, so that, from the great cachalot down to the smallest fish, mollusc, or crustacean, it may be said that all marine nature is at fierce, carnivorous war. This war, too, is, for the most part, cannibalistic in its nature, and this cannibalism is of a peculiarly horrid description, since most fish devour numbers of their own offspring, for which, by the laws of nature, they feel no affection, and which they do not even know. In these latter practices, indeed, the cetaceans, being mammals and very tender parents, do not participate; but there is another honourable exception, and that where we might least of all expect to find it. The sharks, so justly dreaded for their voracity, to which, as is well known, man himself not infrequently falls a victim, are solicitous of their young, with whom, to the number of a dozen or more, the mother swims about and does her best to provide them with food. The pretty little flock gambol and frolic about her, and should anything alarm them, they dart at once into her great mouth, held open to receive them, and disappear down her throat. There they remain till their mother thinks the danger is over, when she opens her mouth again, and they re-emerge. This privilege—and it must sometimes be a valuable one—is also open to the pretty little pilot-fishes which, to the number sometimes of half a dozen, accompany the shark in all its wanderings, and which everybody has read about.