Feather Duster ID?

[tayphor]

Hi all,

I have these inverts that look feather duster-esque but there is no typical tube. Instead there is this spindly looking stuff wrapped around the base. The whole critter is colorless. Any ideas as to what this is?
I took a picture but it's not the greatest. Thanks!

 

[doublejhunter]

Pineapple sponge.

 

[tayphor]

Thanks!