Weird growth on gorgonian

[ana_luciav]

At least I think it is a gorgonian from the pictures I have seen. It was fine and now it has in two of its branches weird white and black growth. I thought maybe I could cut it like wiht a sponge but it has a hard surface, any ideas, what is it how to fix it?
Check out the picture. Sorry if it isnt that good it only let me 50kb

http://reefcentral.com/gallery/data/500/84609strange_growth.JPG