Sponges of the genus Caulophacus look just like little, white mushrooms.
Can you believe that's just about everything I could find out about them
It seems they are found at a whole range of depths from the surface to the deep. Probably in the world, somewhere.
Have you ever had an umbrella and then there's a gust of wind so strong you thought you could fly off like Mary Poppins?
Well, sort of like that, but only for catching the current and whatever little bits of food may be in there.
Come to think of it, that's not how an umbrella 'works' at all! It's more of an unfortunate side-effect. Particularly since it usually results in your umbrella becoming inverted and turning into a good way of holding a puddle above your head. That's not how umbrellas are supposed to work, either.