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The Collaborative International Dictionary
Palaeechinoidea

Paleechinoidea \Pa`le*["e]ch`i*noi"de*a\, n. pl. [NL. See Paleo-, and Echinoidea.] (Zo["o]l.) An extinct order of sea urchins found in the Paleozoic rocks. They had more than twenty vertical rows of plates. Called also Pal[ae]echini. [Written also Pal[ae]echinoidea.]