Under rocks:

Pseudoceros mexicanus

On giant kelp blades:

Look for an iridescent blue sheen, often in a horse-shoe shape. These Syllid polychaete worms are easily overlooked, and even the worm expert, Leslie Harris, wasn't aware of this association. Leslie kindly ID'd these as either genus Eusyllis or Odontosyllis.

This worm has two rows of reproductive material.

Surrounded by southern staghorn bryozoan:

Serpula columbiana, Diaperoecia californica

Surrounded by other worms:

Serpula columbiana and the fragile tubeworm Salmacina tribranchiata

Surrounded by a tunicate:

Two Serpula columbiana and Didemnum carnulentum
On my approach, both serpulid worms retreated into their tubes, leaving only their opercula visible.

Pretty and wedged in a crack:

• Wow! Spectacular pics (-) seahunt 15:36:58 07/14/15 (0)