Ianthina
Pronunciation : I*an"thi*na, n.; pl. L. Ianthin
Part of Speech : E.
Etymology : [NL., fr. L. ianthinus violet-blue, Gr. (Zo?l.)
Definition : Defn: Any gastropod of the genus Ianthina, of which various species are found living in mid ocean; -- called also purple shell, and violet snail. [Written also janthina.]
Note: 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.
Ianthinas.
Source : Webster's Unabridged Dictionary, 1913