Word Study
ianthina
CIDE DICTIONARY
ianthina, n. [NL., fr. L. ianthinus violet-blue, Gr. ; violet + flower.].
Any gastropod of the genus Ianthina , of which various species are found living in mid ocean; -- called also purple shell , and violet snail . [1913 Webster]
" It floats at the surface by means of a raft, which it constructs by forming and uniting together air bubbles of hardened mucus. The Tyrian purple of the ancients was obtained in part from mollusks of this genus." [1913 Webster]
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