Parasitic fungus on agaric mushroom

Description:

a clump of agaric mushrooms growing on a tree stump were covered with a white bloom and some of the caps had yellowish granular structures (pic #3). The underside of the mushroom which appeared to have spaced orange gills was also covered with these granular growth. Every similar looking mushroom was covered with these yellow granules- they could not be wiped away. The mushroom caps looked half withered but felt very tough.