Lactarius pallescens

Lactarius pallescens, commonly known as the pallid purple-staining milk cap, is a Western North American "milk-cap" mushroom, of which the milk turns violet when the flesh is damaged. The fungi generally identified as L. pallescens are part of a complex of closely related species and varieties which have a peppery taste and are difficult to delimit definitively. The gray-brown cap ranges from 3 to 10 cm in width, with a mucilaginous surface, whitish flesh and white latex. The gills are whitish and sometimes slightly decurrent. The viscid stalk ranges from 3 to 8 cm long and 1 to 2 cm wide. The spores are pale yellow to orange, elliptical, and bumpy. The flesh of the mushroom stains lilac. In age, reddish stains develop....read more on Wikipedia.