 The cap of this fungus ( known technically as an <unk> ) is 2 to 4 cm ( 0 @.@ 8 to 1 @.@ 6 in ) in diameter by 2 to 5 cm ( 0 @.@ 8 to 2 @.@ 0 in ) long , with a conical or bell shape . It is folded into longitudinal ridges that often fuse together ( <unk> ) in a vein @-@ like network . The cap is attached to the stem at the top only — hanging from the top of the stipe , with the lobed edge free from the stem — and varies in color from yellowish @-@ brown to reddish @-@ brown ; the underside of the cap is pale . The stem is 6 to 12 cm ( 2 @.@ 4 to 4 @.@ 7 in ) long by 1 to 2 @.@ 5 cm ( 0 @.@ 4 to 1 @.@ 0 in ) thick , cream @-@ white in color , and tapers upward so that the stem is thicker at the base than at the top . Although the stem is initially loosely <unk> with <unk> hyphae , it eventually becomes hollow in maturity ; overall , the mushroom is rather fragile . The spore deposit is yellow , and the flesh is white . 
