ABSTRACT
Some morphological modifications related to nutrition in culture have been observed in marine invertebrate larvae. In echinoids, the effect appears in the length of the echinopluteus arm and the diameter of the echinus rudiment or newly formed juvenile. The size of different stages of development, the duration of pelagic life of planktonic plutei and plutei cultured in the laboratory with natural particles from sea water filtered through 50µm, enriched sea water. Two cases were examined: If the planktonic larvae developed more slowly, development in the sea is thus limited by the available food; If the form of planktonic larvae is comparable to the form of plutei reared on a natural or enriched diet, development is not limited; if the planktonic larvae have a larger size it is because they react to an impoverished ration by an increase the size as we observed for the cultured larvae.
