of Ophiothrix fragilis, [487];
of Echinus esculentus, [517], [528];
of Echinocardium cordatum, [552];
of Holothuroid larva, [564];
of larva of Antedon rosacea, [583];
development of, in Asterina gibbosa, [609]
Axifera, [353]
Axinella, [216], [222], [225];
A. erecta, [216]
Axinellidae, [217]