"How is spawn obtained in the first instance? It is found in a natural state in half-decomposed manure-heaps, in places where horse-droppings have accumulated and been kept dry, in riding-schools, sheds to which horses have long had access, in "mill tracks" under cover, in pastures, in partially decayed hotbeds, &c., and rarely or never in very moist or saturated materials. This spawn, sometimes termed "natural" in this country, and called by the French "virgin spawn," is the best that can be obtained, and should be used in preference wherever it can be found. To use it, all that has to be done is to divide the material permeated by the white spawn into pieces a few inches square, and say an inch or more thick. They will of course break up irregularly, but all should be used, whether of the size of a bean, or nearly that of the open hand. Then they are inserted into the surface of the mushroom-beds in the ordinary way."