About the size of a garden snail, this is the shellfish seen scattered in thousands over upper tidal mud flats. It feeds by sifting organic particles from the mud. The species is remarkable in that it breathes by means of a primitive lung, not gills. It is the only air-breathing marine snail possessing an operculum. The Maoris esteemed this shellfish as food and called it titiko.
by Arthur William Baden Powell, Assistant Director, Auckland Institute and Museum.