30 MUSHEOOMS. 



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

 tion, upward. As the mushroom grows the 

 stem 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 composed 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 hyphge. 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) 



