This is a largely sedentary worm that spends most of it's time under a rock, encased in a jelly sheath. Each of it's segments has hard bristles on it and the ones nearest the head are long and cage like.

Under rocks in the low tide zone in sheltered areas.

Feeds on organic matter through an opening in the jelly sheath.

Photo Credit: Rod Morris. Photos can be purchased from https://www.rodmorris.co.nz/