a. Zool. [a. F. spirivalve, f. L. spīra SPIRE sb.3] a. Of shells: Univalve and spiral. b. Having a spiral univalve shell.
1835. Kirby, Hab. & Inst. Anim., I. ix. 267. Trachelipods…; greatest part of the body spirally convolved,… inhabiting a spirivalve shell.
1836–9. Todd’s Cycl. Anat., II. 384/1. Many of the spirivalve Gasteropoda … are provided with a calcareous plate, which … closes accurately the mouth of the shell.
