All together now

I had to do some intertidal field work this afternoon (18 February 2019).  When I finished, I looked around a bit.  I was starting to focus on this chiton (Lepidozona cooperi), when I noticed something intriguing next to it:

 

My first thought was that the striped object might be the arm of a brittle star.  But when I was able to see it more clearly, I realized it was a polychaete worm.  

I think we've seen this worm before — for example, see the post called "Ruler worm?" from 1 May 2013.  However, this individual appears to be broader.  When I zoomed in, I could see that it's possible she has lots of cream-colored eggs inside?

 

I'll have to ask around for some help with the identity of this intriguing worm.

P.S.  In case you're wondering, the white spiraled animal at the head end (left side) of the worm is a foram (Foraminifera).  The bright pink animal in the same location is a bryozoan (Eurystomella bilabiata).  The paler pink in the lower left corner of the second photo (and above and to the right of the chiton in the first photo) is coralline algae.