growth. Iliis ;irr:iiii;ciii(-'nt is not as rigidlv exact as would be 

 dcsiraMc. Imt it throws those s])e<'ies together that are most 

 closelv I'chited to each othei", and i^ therefore natural. 



The e.-iseiitial characters to be noted in all the species in this 

 geiitts are, gills free from the stem, pink colored before maturity, 

 blackishd)ro\vn or black when fully mature, sjtores brown, and a 

 stem bearint>- a rinc.' or c<^llar. There are manv similar mush- 

 rooms which ai-e not known to be edible but wdiich have pink 

 gills. Their gills, however, never become brown or blackish- 

 brown; their s])ores are pink, and their stom never has a collar. 



25 



