ABSTRACT
This chapter talks about the development of laboratory cultured sea urchins was followed up to metamorphosis (and appearance of juvenile forms) in five species of sea urchins Strongylocentrotus intermedius, Strongylocentrotus nudus, Scaphechinus mirabilis, Scaphechinus griseus and Echinocardium cordatum. The effect of various substances, possessing a neurotransmitter activity and of natural substrates on metamorphosis of larvae has been studied. Glutamine can be used as metamorphosis inducer of S. intermedius and S. mirabilis (100% and 50% activity, respectively). A natural substrate for settlement of S. intermedius larvae was found, namely the sea grass Zostera marina colonized by a calcareous alga Melobesia spp.
