The Universal veil is a mycological term to describe a structure that envelops all or most of some gilled mushrooms. The young, developing button mushroom, which may resemble a puffball at this point, is protected by this egg-like structure. The veil will eventually become ruptured and dispersed by the growing mushroom, but will usually leave evidence of its former shape with remnants including the volva (mycology), or cup-like structure at the bottom of the stalk stipe and patches or "warts" on the cap pileus.