mint green mushroom and sack of ??? eggs??? what is it?

[L2]

I just got a mint green mushroom and right next to him is this sack... Is it a sack of eggs or? I can't figure it out. A dead clam? What is that redish brown sack on the right hand side?

Thanks!
Lloyd

 

[Devilishturtles]

Looks like a sponge to me.