Dictionary entry

Pectostraca

Webster's Dictionary 1913

‖Pec‐tos″tra‐ca (pĕk‐tŏs″trȧ‐kȧ), n. pl. [NL., fr. Gr. πηκτόσ fixed + ὄστρακον shell of a testacean.] (Zoöl.) A degenerate order of Crustacea, including the Rhizocephala and Cirripedia.