30 MUSHROOMS. 



vision of cells, not laterally, but in one direc- 

 tion, upward. As the mushroom grows the 

 stein lengthens, the cap expands and bursts the 

 veil that surrounds it, and gradually gains its 

 perfect shape. 



Every mushroom has a spore-bearing layer 

 of cells, which is called the hymenium. This 

 hymenium is conrposed of a number of swollen, 

 club-shaped cells, called basidia, and close to 

 them, side by side, are sterile, elongated cells, 

 named paraphyses. In the family called Hy- 

 menomycetes there are mixed with these, and 

 closely packed together, one-celled sterile struc- 

 tures named cystidia. 



The basidia are called mother-cells because 

 they produce the spores. 



There is one great group of fungi called 

 Basidiomycetes, so named from having their 

 stalked spores produced on basidia. 



The basidia are formed on the end of thread- 

 like branched bodies which grow at the apex, 

 and are called hyphse. On top of the basidia are 

 minute stalk-like branches, called sterigmata 

 (singular sterigma), and each branch carries a 

 naked spore. They are usually four in num- 

 ber. This group of Basidiomycetes is divided 

 into (1) Stomach fungi (Gasteromycetes), (2) 



