opheliidæ

from The Century Dictionary.

• noun A family of polychætous annelids, having a short body, conical præstomium without appendages but with two ciliated pits, parapodia reduced with two groups of simple setæ and usually with dorsal cirri present and acting as gills. They inhabit the sand, and among the several genera are Ophelia, Ammotrypane, and Polyophthalmus.