. Cyclopedia of farm animals. Domestic animals; Animal products. 636 SHELL-FISH SHELL-FISH grow, with frequent molts, until nearly an inch in length ; then they seek the bottom. In approxi- mately four years they are eight inches long and produce their first batch of eggs, about five thou- sand in number. For artificial rearing, the eggs are removed in the early summer from "berried" females and hatched in floating crates, covered with cotton scrim. Hatching begins in June, and the larval moltings, six in number, consume nine to twenty- five days, according to the temperature (70° to
. Cyclopedia of farm animals. Domestic animals; Animal products. 636 SHELL-FISH SHELL-FISH grow, with frequent molts, until nearly an inch in length ; then they seek the bottom. In approxi- mately four years they are eight inches long and produce their first batch of eggs, about five thou- sand in number. For artificial rearing, the eggs are removed in the early summer from "berried" females and hatched in floating crates, covered with cotton scrim. Hatching begins in June, and the larval moltings, six in number, consume nine to twenty- five days, according to the temperature (70° to 60° Fahr.). There is great mortality among the young, principally from a fungus, the growth of which can be restrained by the use of copper net- ting. The larvae eat lobster and crab liver and crushed menhaden, but not the flesh of herring or beef. The best results come from feeding natural plankton (see page 393), but the mortality is very great. It is still a question whether the mortality under nature is greater or smaller than under artificial conditions. But if the eggs of lobsters that are caught can be saved, evidently natural methods will be supplemented. Laws prohibiting the taking of "berried" lobsters should prove the most efficient means of preventing depletion. At the end of the larval period the young lobsters are turned into the sea to shift for themselves. They do not wander far, and so particular regions can be stocked. Oyster. Ostrea spp. Mollusca. Figs. 641-644. By Julius Nelson. The oyster industry has been considered a fish- ery, but it attains its best development through the application of aquicultural methods. Its inter- ests are in charge of the United States Bureau of Fisheries, state fish commissions, or of special oyster and shell-fish commissions. In 1902, the United States produced nearly twenty-six million bushels of market oys- ters, about five - sixths of the world's product, worth at first cost $15,- 566,805. More than a third of t
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Keywords: ., bookauthorbaileylh, bookcentury1900, bookdecade1920, bookyear1922
