Rhachiglossa \Rhach`i*glos"sa\, n. pl. [NL. See {Rhachis}, and {Glossa}.] (Zool.) A division of marine gastropods having a retractile proboscis and three longitudinal rows of teeth on the radula. It includes many of the large ornamental shells, as the {miters}, {murices}, {olives}, {purpuras}, {volutes}, and {whelks}. See Illust. in the Appendix. [1913 Webster]
Murex \Mu"rex\, prop. n.; pl. {Murices}. [L., the purple fish.] (Zool.) A genus of marine gastropods, having rough, and frequently spinose, shells, which are often highly colored inside; the rock shells. They abound in tropical seas. [1913 Webster]