Coralline Algae

As a native Easterner most often on Western beaches, I am fascinated by the delicate bony seaweed that is so commonly found strewn along the wrack line of the rough and tumble beaches of Northern California.  This is the articulated coralline red algae.  When alive, its joints -- the flexible, noncalcified genicula ("knee" in latin) --  bend with the tidal flow.  When dry, however, coralline algae is delicate and breaks easily into its calcified pieces.