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Show 190 ATLANTIC OCEAN. Dec. 1833. on this part five most minute cups are placed, which seem to act in the same manner as the suckers on the arms of the cuttle-fish. As the animal lives in the open sea, and probably wants a place of rest, I suppose this beautiful structure is adapted to take hold of the globular bodies of the Medusre, and other floating marine animals. In deep water far from the land, the number of living creatures is ext:emely small: south of the latitude 35°, I never succeeded in catching any thing besides some beroe, and a few species of minute crustacea belonging to the Entomostraca. In shoaler water, at the distance of a few miles from the coast, very many kinds of crustacea and some other animals were numerous, but only during the night. Between latitudes 56° and 57° .south ?f Cape Horn the net was put astern several times; rt never, however, brought up any thing besides a few of two extremely minute species of Entomostraca. Yet whales and seals, petrels and albatross, are exceedingly abundant throughout this part of the ocean. It has always been a source of mystery to me, on what the latter, which live far from the shore, can subsist. I presume the albatross, like the condor, is able to fast long; and that one good feast on the carcass of a putrid whale lasts for a long siege of hunger. It does not lessen the difficulty to say, they feed on fish· for on what can the fish feed? It often occurred to me wh~n observino- how the waters of the central and inter- ' . b c tropical parts of the Atlantic,* swarmed with Pteropo~a, rus-tacea, and Radiata, and with their devourers the flymg-fish, and again with their devourers the bonitos and albicores, that the lowest of these pelagic animals perhaps possess the power of decomposing carbonic acid gas, like the members of the vegetable kingdom. While sailing in these latitudes on one very dark night, >If. From my experience, which has been but little, I should say that the Atlantic was far more prolific than the Pacific, at least, than in that immense open area, between the west coast of America and the extreme eastern isles of Polynesia. Dec. 18.'33. PHOSPHORESCENCE OF THE SEA. 191 the sea presented a wonderful and most beautiful spectacle. There was a fresh breeze, and every part of the surface which during the day is seen as foam, now glowed with ~ pale light. The vessel drove before her bows two billows of liquid phosphorus, and in her wake she was followed by a milky train. . As far as the eye reached, the crest of every wave was bnght, and the sky above the horizon, from the reflected glare of these livid flames, was not so utterly obscure, as over the-rest of the heavens. As we proceed further southward, the sea is seldom phosphorescent; and off Cape Horn, I do not recollect more th~~ once ha;Jn~ seen it so, and then it was far from being brilliant. Tins Circumstance probably has a close connexion with the scarcity of organic beings in that part of the ocean. After the elaborate paper* by Ehrenberg, on the phosphorescence of the sea, it is almost superfluous on my part to make any observations on the subject. I may however add, that the same torn and irregular particles of gelatinous matter, described by Ehrenberg, seem in the southern as well as in the northern hemisphere, to be the common cause of this phenomenon. The particles were so minute as easily to pass through fine gauze; yet many~ were distinctly visible by the naked eye. The water when placed in a tumbler and agitated gave out sparks, but a small portion in a watch-glass, scarcely ever was luminous. Ehrenbero- states b ' that these particles all retain a certain degree of irritability. My observations, some of which were made directly after taking up the water, would give a different result. I may also mention, that having used the net during one nio-ht I allowed it to become partially dry, and having occ:sion twelve hours afterwards, to employ it again, I found the whole surface sparkled as brightly as when first taken out of the water. It does not appear probable in this case, that the particles could have remained so long alive. I remark * An abstract is given in No. IV. of the Magazine of Zoology and Botany. |