Page:Popular Science Monthly Volume 35.djvu/686

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THE POPULAR SCIENCE MONTHLY.

bottom is scraped just before leaving port, young goose barnacles attach themselves in such numbers that, owing to their rapid growth, they seriously retard the ship's progress. There is no remedy but to sail on, letting them grow as fast as they will, and removing them when port is reached. Norwegian sailors believe that the barnacle goose hatches out of the goose barnacle, and many have asserted that they have seen the young just on the point of flying out. This belief probably arises from the peculiar scooping motion of the fringed feet of the barnacle while it is obtaining food. Even then a good imagination needs some stretching to be able to see a resemblance to a young bird. When a barnacle is young, it is free-swimming, and resembles a shrimp; but, as it grows older, it attaches itself to some object by a sort of cement, and becomes so changed that, unless its anatomy is carefully studied, no affinities to a shrimp would be imagined. Indeed, early naturalists considered it to be a shell-fish or mollusk. Odd as it may seem, many kinds of animals, at first possessed of free motion, voluntarily attach themselves to some object, and are from that moment imprisoned, having no power of moving from place to place.

Insects are seldom seen in a natural state far from land, but we find a few young forms a little nearer shore, and one of these, a fly larva (Chironomus), is more interesting than the others on account of its remarkable powers of endurance. Experiments were tried, and we found that it would live after being taken out of a vial of alcohol in which it had been kept several hours. Most animals, under similar conditions, will die in five minutes, and the most hardy in twenty. Different poisons were tried, and none were effective. Even caustic potash was resisted for nearly an hour. In the mean time the creature would swim around lively. Such hardiness is probably found in no other animal. In addition to these more interesting forms, there are hundreds of species each presenting some especial peculiarity which distinguishes it from the rest, and all have interesting habits and points of structure. The waters of the Gulf Stream gradually merge into those of the ocean on either side, and, while there are some peculiarly tropical forms which never go outside of the warm water, most are likely to be taken on either side in the colder waters, and there are many which are found both near shore and in the Gulf Stream. After long-continued southerly winds, tropical forms are at times cast on shore; and vessels passing through the Gulf Stream frequently bring into port, attached to their bottoms, crabs and shrimps which normally do not live in the inner region. The warm waters of this part of the ocean are very favorable to rapid growth, and the animals there are tropical. Washing the shores of Florida, the Gulf Stream serves to transport its