Tubes and slippers on the beach

I've heard from several people that pyrosomes have been washing ashore on beaches — in Monterey and Bodega Bay, California and in Seaside, Oregon.  We saw some pyrosomes ourselves last night (22 February 2017) on Salmon Creek Beach:

 

We estimated there were over 1,000 pyrosomes washed up along about a 1-km stretch of beach.

Below is a closer view.  You might recall that pyrosomes are a type of pelagic tunicate, related to sea squirts.  [For an introduction to pyrosomes, review the "Fire bodies" post from 8 December 2014.]

 

We encountered a variety of sizes (most of them were on the larger end of this size range):

 

I've received a few questions about how to tell pyrosomes from Corolla spectabilis pseudoconchs.  So for anyone who's been puzzling over either one, here's a side-by-side comparison.  Note the overall shape (oval vs. elongate) and color (clear and transparent vs. pinkish and opaque) and structural differences (slipper-shaped vs. tubular).

 

And if you haven't seen it yet, there's an introduction to Corolla on the "Gelatinous thimble" post on 11 August 2012.