This is a globular, paper thin and transluscent white, just like a bubble! The animal covers most of the shell and is drab, greyish black, flecked with brown. Some animals can be very dark.

Mudfalts to seagrassbeds to salty coralline algal turf in tide pools, in harbours and sheltered bays. Strictly intertidal.

It feeds on green algae such as Ulva and also scrapes the diamotaceous film from sea grass and muddy sediments.

Its sausage-shaped yellow egg masses can be extremely abundant.

NZ Coastal Marine Inverts Vol 1
http://www.seaslugforum.net/find/hamizela accessed 17/02/14
Photo Credit (animal): Rod Morris. Photos available from www.rodmorris.co.nz