1. The Cultivated Mushroom 



In the United States the term "mushroom" refers commercially 

 to but a single species (Agaricus campestris) of the fleshy fungi, 

 a plant common throughout most of the temperate regions of the 

 world, and one everywhere recognized as edible. From the time 

 of Pliny, and perhaps much earlier, this plant has been sought as 

 an article of diet, and it has been cultivated for many centuries. 

 In the vicinity of Paris it has certainly been cultivated in some 

 quantity since the sixteenth century; and, in paintings of market 

 scenes by old masters of the seventeenth century, a basket of 

 mushrooms frequently finds a place in the composition, thus show- 

 ing that at that time the sale of mushrooms was generally recog- 

 nized in a commercial way.- 



The fully expanded plant, or mature mushroom (sporophore), 

 of Agaricus campestris is well known to every one.^ It consists of 

 a centrally placed stock or stipe of from 2 to 6 inches in height, 

 usually not more than one inch in diameter, and on the end of this 

 stipe there is borne an umbrella-shaped or cap-shaped portion 

 known as the cap or pileus. The diameter and thickness of this 

 pileus vary in different races or varieties of the cultivated form, 

 and also with the conditions of the environment under which it 

 is produced. The general color of the plant varies in the different 

 varieties from an almost pure white, or cream, to the forms which 

 are deep brown, at least with reference to the upper surface of the 

 cap. The stem'is usually cream or white, and bears on its upper 

 extretriity near the cap a ring known as the annulus, which annulus 

 forms a covering and a protecting layer for the delicate under sur- 

 face of the cap, to the edges of which it, was attacked previous to 

 the rapid expansion and maturit;^ of the latter. The under surface 

 of the cap is provided with leaflike or gill-like projections, reach- 

 ing for the most part from the stem to the periphery of the cap. 

 These are termed gills, or "lamellae." They are constantly pink 

 in color in the white or cream-colored species up to the time of (and 

 sometimes even a day after) the separation of the ring from the 

 cap. Subsequently these gills turn brown and even a deep brown- 

 ish black. In the brown variety the gills are at first grayish brown 

 but they also become almost black with age. 



2. Market Conditions 



The successful cultivation of mushrooms in America has not 

 been so general as in most of the European countries. It is in 

 France and England that the mushroom industry has been best 

 developed. France is, properly speaking, the home, of the present 

 mushroom industry. Unusual interest has been shown in the , 

 United States in the growth of mushrooms within the past few 



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