Word Study
arthrostraca
CIDE DICTIONARY
arthrostraca, n. pl. [NL., fr. Gr. 'a`rqron joint + a shell.].
One of the larger divisions of Crustacea, so called because the thorax and abdomen are both segmented; Tetradecapoda. It includes the Amphipoda and Isopoda. [1913 Webster]
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