( n. pl. )
A large division of Mollusca, including all except the bivalves; -- so called because the head is distinctly developed. See Illustration in Appendix.
( n. pl. )
A large division of Mollusca, including all except the bivalves; -- so called because the head is distinctly developed. See Illustration in Appendix.
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012