FUNGI 



155 



tures commonly called mushrooms are the spore-bearing 

 branches. In pulling up a mushroom, fragments of the 

 mycelium may often be seen attached to it, looking like 

 small rootlets. In the following description, however, the 

 word mushroom will be used in its ordinary sense. 



The mushroom has a stalk-like portion (stipe) and an 

 expanded umbrella-like top (pileus) . On the under side of 

 the pileus there are found thin, radiating, knife-blade-like 

 plates (gills) (Fig. 147, A). The surface of the gills consists 

 of a layer of peculiar club-shaped cells called basidia (Fig. 

 147, B). From the broad end of each basidium usually 

 four delicate branches 

 arise, each producing at 

 its tip a minute spore 

 (Fig. 147, C). The ripe 

 spores shower down from 

 the gill surfaces, germinate, 

 and produce new mycelia. 



The most common edi- 

 ble mushrooms grow in 

 fields and pastures; but 

 there are numerous mush- 

 rooms in the deep woods, 

 in fact wherever there is 

 decaying organic material. 

 It has been found impos- 

 sible to give directions for 

 distinguishing edible and 

 poisonous forms that can 

 be used by those who are 



not familiar with mushrooms. It is exceedingly unsafe for 

 an inexperienced person to gather wild mushrooms for eat- 

 ing, for some of the deadliest forms resemble in a general 

 way those commonly eaten. 



The mushrooms with gills form a very large group, 



FIG. 148. A common pore-fungus. 

 After GIBSON. 



