DR. HUBERT LYMAN CLARK‘S large work, "Echinoderms from Australia", was reviewed in Nature of September 24, 1938. That review and the obituary notice of Dr. Clark in Nature of September 20 ...

A class of echinoderms that includes crinoids, characterized by a cup-like body and feathery arms. Calyx: The cup-shaped part of a crinoid that houses the internal organs. Echinodermata: A phylum ...

Sea stars, sea urchins, sand dollars and sea cucumbers are all members of the phylum Echinodermata. Echinoderm means “spiny skin” in Greek. Echinoderms are found in ocean ecosystems worldwide ...

They belong to the Echinoidea, one of the five classes of the phylum Echinodermata, the others being holothurians, crinoids, starfish and brittlestars. Like all echinoderms, echinoids have a skeleton ...