 The shape of the cap is initially convex before later becoming broadly convex to eventually flattened in maturity ; the diameter of the cap is typically between 3 and 15 cm ( 1 @.@ 2 and 5 @.@ 9 in ) . The cap surface is dry , with a velvet @-@ like texture , although in age it can become rimose ( developing a network of cracks and small crevices ) . The cap color is initially black to dark grayish @-@ brown ; young specimens can have a whitish bloom ( resembling a dusting of fine powder ) on the surface . Fruit bodies , especially young specimens , tend to be free of maggots and other insect larvae . As the mushroom matures , the bloom disappears and the color fades to become grayish to grayish @-@ brown . The cap flesh is whitish , but after it is cut or injured , it will stain pink to reddish @-@ gray , and eventually turn black . 
