Figure 131.—Lactarius indigo. One-third natural size, showing gills.
This is one of our most striking plants. No one can fail to recognize it, because of the deep indigo blue that pervades the whole plant. I have found it in only one place, near what is known as the Lone-Tree Hill near Chillicothe. I have found it there on several different occasions.
The pileus is from three to five inches broad, the very young plants seem to be umbilicate with the margin strongly incurved, then depressed or funnel-shaped; as the plant ages the margin is elevated and sometimes waved. The entire plant is indigo blue, and the surface of the cap has a silvery-gray appearance through which the indigo color is seen. The surface of the cap is marked with a series of concentric zones of darker shade, as will be seen in Figure 130 especially on the margin; sometimes spotted, becoming paler and less distinctly zonate with age or in drying.
The gills are crowded, indigo blue, becoming yellowish and sometimes greenish, with age.
The stem is one to two inches long, short, nearly equal, hollow, often spotted with blue, colored like the pileus.
It is edible but rather coarse. Found in open woods July and August.