268 GENERAL BOTANY 



kind of fruit body, which expands, produces spores, and dies 

 down again in a few days, while the real lasting and perennial 

 portion of the plant is the feeding submerged mycelium within 

 the soil. 



The spore-bearing mushroom fruit is definitely adapted to 

 the production and dispersal of large numbers of asexual 

 'spores. Its parts are the stipe, or stalk, the pileus, or umbrella, 

 and the lamellce, or gills. The stipe bears the pileus at its apex 

 and serves to lift it into the air when the spores are ripened and 

 ready to be shed. The pileus bears the lamellae, or gills, on 



Pileus 



55*^ . ^S^^^^^s^ 



Pileus 



I 



Annulus 

 Stipe 



Mycelium 



FIG. 147. Diagrammatic figures of young and mature mushrooms 

 growing in the soil 



Note the soil mycelium similar to that of Rhizopus in bread (Fig. 140). Adapted 

 from Buller's "Researches on Fungi " 



its under surface as radiating plates which extend from the 

 stipe to the margin of the pileus and greatly increase the spore- 

 bearing surface of the mushroom fruit, since the spores are 

 borne over the entire surface of each lamella. Buller estimated 

 that a single lamella of Coprinus comatus produced about 

 24,480,000 spores and that all of the lamellae of this mushroom 

 bore approximately 5,240,000,000 spores. 



When the mushroom is young (Fig. 147), the pileus is bent 

 down like a folded umbrella, thus protecting the young lamellae 

 and spores during the early stages of their development. Some 

 mushrooms have a further protection for the lamellae and spores 

 in the form of a delicate veil composed of hyphae which stretch 

 from the edge of the pileus to the young stipe, so that the lamellae 

 are inclosed in a chamber away from the outside air. As the 



