 Initially white, the surface of the peridium (spore case) is densely covered with short spines; the spines eventually fall off in irregular sheets, exposing the smooth, brown underlying surface.Mature fruit bodies form a small opening at the top through which spores are released.The internal spore-bearing tissue, the gleba, is initially white and firm, but becomes greenish-brown and then greyish-brown and powdery at the mushroom matures.