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its a mushrOOm...
The fungi are divided into a number of classes, each of which is again subdivided into sub-classes, series, and families. The family of Basidiosporeae include the largest and most conspicuous of the fungi and all of the mushrooms and toadstools. It is commonly believed that mushrooms are edible and that toadstools are poisonous; in reality, however, no such distinction should be made. The plants of the Hymenomycetes are characterized in general in that they arise from a mass of colorless threads, known as "mycelium" or "spawn," produced in the ground, bark of trees, etc. Their first appearance above ground is marked by the production of small solid balls (called buttons), which gradually enlarge, and at length shoot up into a stem or stipe bearing at its summit the umbrella top or "pileus," which is at first closed around the stalk like a closed umbrella and then expands more or less widely, according to the species. The under side of the pileus is the part which bears the spores, which correspond to the seeds of higher plants. In some cases the under surface consists of a series of gills resembling knife blades, which radiate from the top of the stalk to the circumference, like the spokes of a wheel, as in Agaricaceae; in others it consists of a mass of small pores or tubes packed closely together, side by side, as in Polyporaceae; in others of teeth, as in Hydnaceae; in others only slightly wrinkled or undulated, as Thelephoraceae, etc. The Basidiosporeae include about 14,000 species which are included in nine orders and subdivided info twenty-five families. A few of the important are the following:
1.—Agaricaceae (the mushrooms and toadstools proper) comprises about 4600 species, some of which are poisonous, as the Amanitas (Fly and Deadly Agarics) Lactarius (with a milky juice), whereas others are edible, as Agaricus (Psalliata) campestris L., the common mushroom, Cantharellus cibarius, Fr., etc.
2.—Polyporaceae (pore-fungi) includes about 2000 species, many of which are parasites on trees and destructive to timber; some are edible, as Boletus edulis Bull., whereas others are poisonous, as B. satana Lenz.
3.—Hydnaceae (teeth-bearing fungi); Most of the species are too small and woody to be eaten. Hydnum repandum forms "fairy rings" in woods.
4.—Thelephoraceae: Most of the species are small, and the larger species are tough and leathery.
5.—Clavariaceae (coral-shaped fungi) includes some large fungi; none are poisonous and some, as Clavaria flava Schaeff., are palatable.
Of these, the most important group are the Agaricaceae, both from the point of view of the toxicologist and the epicure.
It is not possible in this limited space to even mention the various poisonous and edible fungi that experience has demonstrated as such. The number of species which have been eaten or experimented with, however, is small compared to the number recognized by botanists. Many students of fungi have formulated rules for distinguishing edible from poisonous fungi. "The different popular tests for distinguishing edible from poisonous fungi, such as, for instance, the blackening of a silver coin or spoon when placed in a mass of poisonous fungi while they are being cooked, are all absolutely worthless." The only safe rule is to use no mushroom which the collector is not absolutely sure from previous experience is edible.
The common mushroom (Agaricus campestris L.. is practically the only species cultivated in this country, and is the only fresh species sold in the northern markets during the winter months. It is found wild in open grassy fields and pastures in great abundance in August and September. It is not common on the mountains, never found in woods, and never grows on trees or fallen trunks. The color of the stalk and pileus varies from a whitish shade to drab, but the color of the gills, a point which should never be overlooked, is at first pinkish and then a brownish-purple. The stalk is cylindrical and solid, and has, rather more than half way up, a membranous collar called the ring; but there is no membrane or scales found at the base of the stalk, which appears to come directly out of the ground. "In specimens which are not fully expanded there is a thin membrane or veil which extends from the stalk to the margin of the pileus. When the veil is ruptured, exposing the gills behind, a part remains attached to the stalk, forming the ring already referred to. In older specimens the ring shrinks, but generally a mark remains showing where it has been attached."
Two of the most poisonous forms resembling the common mushroom, and which have been eaten in mistake for it, are the deadly agaric and fly agaric.
The fly agaric (Amanita muscaria (L.) Pers.., so called because decoctions have been used for killing flies, is in some localities much more abundant than the common mushroom. It is seldom found in the grassy pastures preferred by the common mushroom, but more gener