Nearly all of the Arctic Ocean adjacent to the coast of America is as yet unexplored, and we have therefore no direct testimony as to its flora and fauna. We may reasonably assume, however, that the life is there practically the same as in the waters of similar depth to the north of Eurasia. Nordenskioeld, in his narrative of the voyage of the Vega, speaks of decapods, worms, mussels, crustacea, and asteroids which crawled in myriads over the beds of clay and sand at the bottom of the Kara Sea. A detailed account is given of one unusually successful haul of the trawl when it brought up large asteroids, sponges, crinoids, holothuria, a gigantic spider, masses of worms, crustacea, etc. This was the most abundant yield of the trawl-net at any one time during the voyage of the Vega on the north coast of Asia, and that, too, from the sea off the northern extremity of the continent. The temperature of the water at the surface was from zero to -1.4 deg. C. (32 deg. to 29.48 deg. F.), and at the bottom from -1.4 deg. to 1.6 deg. C. (29.48 deg. to 34.88 deg. F.). In this connection the same distinguished naturalist remarks: "It is singular that a temperature under the freezing-point of pure water should be advantageous for the development of an animal life so extremely rich as that which is found here, and that this animal life should not suffer any harm from the complete darkness which during the greater portion of the year prevails at the bottom of the ice-covered sea." To persons who have never visited the far north the statements that travellers in those regions give in reference to the abundance of life in the sea seems scarcely to be credited. The assertion, however, that comparing equal areas in the most populous tropical sea and in portions of the Arctic Ocean, the amount of life, or the tons of living animal matter per square mile in the two regions, would be in favour of the northern station is probably true. In addition to the direct evidence indicated above as to the prolific invertebrate life of the cold waters of the north, we have still more impressive testimony from the vast numbers of birds and large-sized mammals which subsist on this abundance, or feed on fishes, which in turn obtain their subsistence from the invertebrate realm. Every rocky island and headland at the north is a breeding-place for sea-birds. They are to be numbered by millions, yet their daily food is gathered from the surface of the sea. The seals live in large numbers about all the arctic shore, and the walruses, each individual weighing about a ton, occur in herds; while whales and narwhals inhabit the same waters. The presence of such numbers of large mammals is proof that the life on which they subsist is abundant. THE SUBMARINE TOPOGRAPHY OF THE CARIBBEAN REGION