The experiments with oysters are full of interest. In Chesapeake Bay, where the best natural oyster beds were found, the demands on them were so great that the supply began to fail. In 1904 only a little more than one-fourth as many were produced as in 1880. The natural oyster beds were then marked and set aside as public fishing grounds. These are to be used by whoever wishes but under strict protective rules. All other ocean beds may be planted with oysters by any one who leases the privilege from the state, and the right to collect the oysters from a certain bed belongs to the person who leases it as fully as does property on land. Louisiana had a small number of natural beds. About ten years ago the planting of oyster beds began, and soon 20,000 acres had been planted. Conditions were particularly favorable, and within two years after the eggs or spawn were placed it was found that oysters three and a half to four inches in size had grown in quantities of 1,000 to 2,000 bushels per acre. For a long time it has been the custom of fishermen to fatten their oysters by transplanting them to new beds where the food is abundant, and in a short time the oysters are much plumper, it takes fewer of them to make a quart and they also sell at a higher price, because they are of the finest quality. These rich food beds are not plentiful, and many dealers are compelled to put small oysters on the market. The Bureau of Fisheries has made a study of these food beds, and by using fertilizer, such as farmers use on their land, have been able to make such beds of sea-plants grow where they do not naturally exist. These experiments have been tried only a short time, but the results have been entirely satisfactory, and it is hoped that before long, rich oyster beds may be made to grow in any part of the ocean where oysters will thrive. In the Great Lakes the fishing is so heavy that it is probable that the supply of perch and white fish would be very low by this time if fish-culture had not been carried on to so great an extent. White fish, lake trout, pike and perch may be hatched in such large numbers as to keep the fisheries up to their present yield. Another important work of the Fisheries Bureau is to keep up the supply of cod for the great fisheries on the New England coast. For the last twenty years profitable shore cod fishery has been kept up on grounds that had been entirely exhausted before and also where cod had never been found before. At the wharves, government officers from the Fisheries Bureau board the fishing boats when they come in and take the eggs from the fish. These are taken to the government hatchery and either the eggs or the young fish are put back into the sea, and so keep up an unending supply.