Pileus at first nearly hemispheric, soon broadly convex, nearly plane or centrally depressed, pruinose and minutely pulverulent, dark crimson or purplish, sometimes darker in the center than on the margin, rarely striate on the margin when old, flesh white, pinkish under the cuticle, taste mild; lamellae moderately close, adnate, white when young, pale yellow when old; stem equal, solid or slightly spongy in the center, colored like or a little paler than the piles, usually white at the top and bottom, rarely entirely white; spores pale yellow, globose, .0003 of an inch broad. This russula is a beautiful and easily recognizable species, though somewhat variable in its colors. The cap is at first nearly hemispheric, but it soon becomes convex and continues to expand till it is nearly plane or centrally depressed. The margin is even when young and generally remains so in maturity, but sometimes it becomes radiately striate. The surface appears to the naked eye to be pruinose or covered with a bloom, but under a lens it is seen to be dusted with minute particles which, under the action of water, are separable and give reddish stains to any white surface against which the moistened cap may be rubbed. This pruinosity is one of the best distinguishing features of the species. A little boy once went with his mother to look for mushrooms. They came on a group of Mary’s russula and the boy, noticing the bloom on the cap and recognizing in it a resemblance to the bloom of plums, cried out in childish glee “plummies, plummies.” He was evidently a close and thoughtful observer and could distinguish at sight this russula from all others. The flesh of the cap is white, but has a pinkish tint immediately beneath the cuticle which is separable on the margin but adnate in the center of the cap. The taste is mild, but occasionally a specimen may be found in which it is slightly and tardily acrid. The color varies from deep crimson to purple. The center is sometimes more highly colored than the margin and in the purple specimens the margin is old plants is apt to fade to a whitish color and to become striate. The gills are white when young but with advancing age they become yellowish. They are nearly all of full length and are therefore wider apart at the margin of the cap than at the stem. A few are forked at the base and the interspaces are veiny. The stem is generally cylindric but occasionally tapering downward or pointed at the base. It appears to the naked eye to be smooth but under the lens it is slightly pulverulent. It is solid or slightly spongy and white within and colored like or a little paler than the cap externally except at the ends where it is white. Forms occasionally occur in which the stem is entirely white. The cap is 1-3 inches broad; the stem 1-2 inches long, 3-5 lines thick. It grows both in woods and in open grassy places and is found in July and August. It is not as highly flavored as some other russulas but I have no hesitation in placing it among the edible species.