MUSHROOM GROWING 



full prime, or somewhat later, the surface 

 becomes distinctly marked into areas as 

 shown in the accompanying illustration. As 

 the plant dries in the field, the outer wall, 

 or peridium, peels off in areas, gradually 

 the mass of purplish spores and tissue wear 

 away, and there persists for months a basal 

 saucer-like, or beaker-shaped, sterile basal 

 part, from which character the name of the 

 species is derived. 



Calvatia gigantea (Plate XP, c) is, as its 

 name implies, the largest of all the fleshy 

 fungi. It often measures from 12 to 18 

 inches in diameter, and specimens more 

 than two feet in diameter have been re- 

 ported. The sporophores are vertically 

 compressed, especially when more than 

 about ten inches in lateral diameter, so that 

 the mature puff ball is ordinarily strongly 

 oblate spheroidal. This species is widely 

 distributed throughout the United States, 

 but it is not so constantly abundant as is 

 Calvatia cyathiforme. It may be found in 

 gardens, pastures, or fields, and occasionally 



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