Less manure is used in these cellars than we generally see in the mushroom-houses of England, and the surface of each bed is covered with about an inch of fine white stony soil.
The mushroom usually grown in gardens or hot-beds, in cellars, sheds, &c., is a distinct variety known as Agaricus hortensis.
Paris mushrooms are cultivated in enormous quantities in dark underground cellars at a depth of from 60 to 160 ft.
The stable manure is taken into the tortuous passages of these cellars, and the spawn introduced from masses of dry dung where it occurs naturally.
The equable temperature of these cellars and their freedom from drought is one cause of their great success; to this must be added the natural virgin spawn, for by continually using spawn taken from mushroom-producing beds the potency for reproduction is weakened.