sentences:  Unlike some other puffball species, the peridium does not differentiate into a distinct exoperidium and endoperidium; rather, the outer layer develops the features of a pseudoparenchyma (a tightly organised tissue where the tightly packed cells resemble plant parenchyma) as the radial and tangential hyphae become interweaved.In time, the peridium dries and falls off in flakes to expose the underlying gleba.The brain-like surface folds and mature olive-brown gleba are characteristic of "Calvatia craniiformis", but younger puffballs that have not yet developed these characteristics may be difficult to identify to species.