ABSTRACT
Overfishing of the natural riches of the ocean has resulted in appreciable depletion of its organisms. The habitats and numbers of many marine bivalve molluscs and echinoderms have been reduced. These animals have been significant sources of food since ancient times. Consequently, aquaculture has assumed greater importance. There are problems, however, particularly in the cultivation of hydrobionts having ad,-anced locomotore apparatuses. It is far more economical and expt>dient to culture nonmobile settled organisms, for example, bivalve molluscs.
