OF MASSACHUSETTS. 133 



As the oyster will not grow on all kinds of bottom, but demands a 

 firm soil, free from soft mud and shifting sand, the oyster area of the 

 State is naturally limited. Usually but part of an oysterman's grant 

 is suitable for the cultivation of oysters, and he is forced to let the 

 rest of the territory lie idle, unless he can, with shells or gravel, arti- 

 ficially change this waste area into suitable ground. Shifting sand per- 

 haps can never be made suitable for oysters; but many acres of soft 

 mud can be made productive, if the oystennan only has a reasonable 

 guarantee that he would receive the results of his labor. 



While the oyster culture is limited by the nature of the bottom, it 

 is also restricted by other conditions. The salinity of the water has 

 much to do with the rapidity of growth, and the oysters seem to thrive 

 in localities where a slight amount of fresh water enters. The amount 

 of food in the water is the principal factor in the rate of growth, and 

 to this is due the fact that the rate of growth varies considerably in 

 different localities. As a rule, the beds with good circulation of water 

 (i.e., currents) show the more rapid growth. 



II. Collecting the "Seed." The term "seed" is applied to one, 

 two, three and even four year old oysters which the oystermen plant 

 on their grants. These grants are in reality salt-water gardens, requiring 

 constant supervision; and the obtaining of the "seed" for planting 

 is a most important consideration. The gathering of the oyster " seed " 

 is a simple process, but one which requires much research. 



Early in the summer, usually during the months of June and July 

 in these waters, the Massachusetts oyster spawns. Both sperm from 

 the adult male and the eggs from the adult female oysters are extruded 

 in considerable quantities into the water, and there the eggs are ferti- 

 lized. As fertilization is somewhat a matter of accident, undoubtedly 

 the great majority of eggs never develop. The fertilized eggs pass 

 rapidly through various changes in the course of a few hours, and 

 emerge as microscopic embryos, with thin, transparent coverings. At 

 this period these forms are free swimming, and are found in great 

 numbers in the water. They are extremely delicate, and great quanti- 

 ties are destroyed by natural agencies, such as cold storms, sudden 

 changes in temperature, etc. They likewise are subject to the depreda- 

 tions of all sorts of marine creatures, and comparatively few in pro- 

 portion survive. The survivors, after leading this free-swimming 

 existence for several days, settle to the bottom, where they attach them- 

 selves by a calcareous fixative to stones, shells, pieces of wood, etc. 

 Here, unless buried by silt and soft mud or killed by exposure, poison- 

 ous pollution, etc., the young oyster rapidly becomes of a size suitable 

 for planting. 



The economic utilization of this scientific knowledge is as follows: 

 shells offer a very good surface for the attachment of the young oyster, 

 and many thousand bushels are annually strewn over the bott.om pre- 

 vious to the spawning season. Considerable judgment is needed in 



