AGA'RICUS is the botanical name by which all the species of mushrooms, properly so called, are collectively known. This genus consists, according to the latest writers, of not fewer than a thousand species, inhabiting meadows, heaths, rocks, and masses of decay ing vegetable matter, in all parts of Europe, and in many other parts of the temperate regions of the earth. Among them a large pro portion are poisonous, a few are wholesome, but by far the greater number are altogether nnknown in regard to their action upon the human constitution.
Agaricus Campestris, the common mush room, is the species that is so frequently raised artificially for food. This is readily known in any state by its fragrant odour, by which alone it may be always recognised, and the absence of which is extremely suspicious. When in a. very young state, it resembles little snow-white balls, which are called but tons ; afterwards it acquires a stalk, separates its cap, and becomes shortly conical, with liver-coloured gills, and a white, thick, fleshy cap, marked with a few particles of gray. At
a more advanced age, the cap is concave, the colour gray, and the gills black ; in this state it is called aflap. Mushrooms appear in the fields chiefly after Midsummer, in the months of July, August, and September. They are indigenous, and spring up abundantly in fields where cattle have been pastured. Much care is bestowed, in some districts, in the artificial culture of mushrooms.
Agaricus pratensis, or oreades, the fairy-ring 'Mushroom, is so well known by its popular designation as to require no description. It may easily have gained that name ; for, in former times, there would doubtless be great difficulty in imagining how such productions could spring up in a few hours in the regular rings they appear in, without the aid of some supernatural agency. The use to which this species is usually applied is that of being powdered and mixed with rich sauces, after having been previously strung upon a line, And dried in the shade.