Abstract
General protein patterns revealed by isoelectric focussing support the view that K. scalarina, K. rhytiphora and K. peroni are distinct and valid species. Differences were reveal ed when the middle mantle folds of the three species were compared using SEM. Comparison of monthly gonad indices for the three species indicated distinct spawning periods with some overlap. K. rhytiphora spat were found bysally attached to live and empty adult shells in Oyster Harbour during March and April 1979. Zonation patterns of the three species showed considerable overlap, with K. rhytiphora and K. peroni occupying almost identical zones and K. scalarina extending higher up the shore.