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Tectibranchiata
CIDE DICTIONARY
Tectibranchiata, n. pl. [NL., fr. L. tectus (p. p. of tegere to cover) + Gr. a gill.].
An order, or suborder, of gastropod Mollusca in which the gills are usually situated on one side of the back, and protected by a fold of the mantle. When there is a shell, it is usually thin and delicate and often rudimentary. The aplysias and the bubble shells are examples. [1913 Webster]
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