The pileus is fleshy, but the flesh of the stem is of different texture from that of the pileus, veil universal, concrete with the cuticle of the pileus, and fixed to the stem, forming a ring which soon disappears in some species; the stem is readily separated from the cap and the gills are free from the stem or slightly adnexed, white at first, then pink, afterwards purple-brown.
All the species grow in rich ground, and it includes many of our valuable food mushrooms.
Agaricus campestris. Linn.
The Meadow Mushroom. Edible.
Figure 248.—Agaricus campestris. Two-thirds natural size.
Campestris, from campus, a field. This is perhaps the widest known of all mushrooms, familiarly known as the "Pink-gilled mushroom." It is the species found in the markets. It is the only species which is sure to respond to the methods of cultivation.
It is the same species which is bought in cans at the store.
In very young plants the pileus is somewhat globular, as will be seen in the small plants in the front row in Figure 248. The edge is connected with the stem by the veil; then round convex, then expanding, becoming almost flat; surface dry, downy, even, quite scaly, varying in color from creamy-white to a light-brown; margin extending beyond the gills, as will be seen in Figure 249 in the one on the extreme right.