TOADSTOOLS 229 



lar layer, and when mature become ruptured by the rapid 

 growth of their central tissues, resulting in the formation 

 of a stalk which carries up the slimy mass of spores to 

 some distance above the ground. The intolerable odor 

 of most of the species has earned for them their inelegant 

 but quite appropriate common name. 



384. The Toadstools (Order Agaricales). The fruits 

 of these plants in some respects are the highest of the 

 Carpomj'ceteae. They are not only of considerable size 

 (ranging from 1 to 20 centimeters, or more, in height), 

 but their structural complexity is so much greater than 

 that of the other orders that they must be regarded as the 

 highest of the fungi. Like the Puff-balls, they produce 

 an abundance of vegetative filaments (mycelium) under- 

 ground or in the substance of decaying wood. These 

 filaments are loosely interwoven, becoming in some cases 

 densely felted into tough masses or compacted into root- 

 like forms. While mostly saprophytic some appear to be 

 parasitic, especially on the woody tissue of trees which are 

 rotted by them. Sooner or later these underground 

 filaments produce the spore fruits, which are mostly 

 umbrella-shaped, as in common Toadstools and Mush- 

 rooms, or of various more or less irregular shapes, as in 

 the Pore fungi, Coral fungi, etc. 



385. The Mushrooms of the markets (Agaricus cam- 

 pcstris) so connnonly cultivated by gardeners, may illus- 

 trate the mode of development of the Toadstools (Family 

 Agaricaceac). The vegetative filaments compose the so- 

 called ''spawn" which grows through the decaying matter 

 from which it derives its nourishment. Upon this at 

 length little rounded masses of filaments arise, which be- 

 come larger and larger and are the young fruits. The 

 circular spore-bearing layer is first internal and su])ter- 

 ranean as in the Stink-horns, but it is brought above 



