What is this plant?

It's definitely a macroalgae of sorts. Maybe a Halymenia species? The bulbous ones on the bottom look like Botryocladia.
 
How about this Gracilaria curtissae.
Gcurtissae.jpg
 
Hmm, looks more accurate than my initial guess. Could be either without being able to examine it up close (really close)
 
That's part of the problem I was talking about. Unless you look at most of these things very, very carefully and even under a dissecting microscope, they are extremely difficult to differentiate. I don't see how phycologists do it.
 
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