 Fruit bodies are irregularly top @-@ shaped to roughly spherical , measuring 7 – 17 cm ( 2 @.@ 8 – 6 @.@ 7 in ) wide by 6 – 12 cm ( 2 @.@ 4 – 4 @.@ 7 in ) high . It has a two @-@ layered peridium . The outer layer of the peridium ( the exoperidium ) is thick and leathery ( except where it thins toward the base ) , measuring 5 – 10 mm ( 0 @.@ 2 – 0 @.@ 4 in ) thick . It is divided into irregular three- to six @-@ sided , low pyramids that are usually blunt , but sometimes pointed . The pyramids are 5 – 8 mm thick . They have parallel markings , a feature Morse attributed to the differences in growth rate caused by variations in daytime and nighttime temperatures . The pyramid centers have short brownish hairs . The pyramids cover the entire peridium except for near the base , where it is smooth . Warts on the surface of young fruit bodies may be disproportionately thick . 
