216 NEW YORK STATE MUSEUM 



on certain specialized cells called basidia (basid ium in the singular) 

 on each of which four spores usually develop. In the morels, these 

 specialized cells are elongated into cylindrical membranous sacks 

 called asoi (ascus in the singular), in each of which eight spores 

 usually develop. In germination the spores send out slender 

 threads or filaments called mycelium by botanists, but commonly 

 known as spaion. The mycelium permeates the soil or other 

 substance on which the mushroom grows and under favorable 

 circumstances develops a crop of mushrooms of its own species. 



The method and place of spore development furnishes the basis 

 for the primary classification of fungi. The best way to acquire 

 a knowledge of our edible mushrooms is to study them in the 

 light of the primary characters employed in botanical classifica- 

 tion and, therefore, in their natural relations to each other. It is 

 my plan to arrange and describe them in their respective classes, 

 families and genera. It will be seen that the species here 

 described are all included in three great groups or classes, whose 

 names and distinguishing characters may be expressed in the 

 following general manner : 



Gasteromyceteae. Fungi whose spores are produced in the 

 interior of the plant. Example. Puff balls. 



Discomyceteae. Fungi whose spores are produced on the 

 upper or exterior surface of the cap and are contained in delicate 

 membranous sacks. Example. Morels. 



Hymenomycetese. Fungi whose spores are produced on the 

 lower surface of the cap. Example. Common mushroom. 



In the last class there are a few species in which no cap is 

 developed. In these the spores are produced on the exterior of 

 upright simple stem-like plants, or of the branches of upright 

 bush-like plants, or on the upper surface of jelly-like irregularly 

 expanded plants. None of the gelatinous plants will be 

 described and only a few species of the other exceptional cases. 

 These species all belong to the single genus Clavaria. 



The spore-bearing surface, or hymenium, is generally recog- 

 nizable, even to the naked eye, by its smooth, delicate, waxy 

 appearance, which is quite unlike that of the sterile surfaces. 



In most of the cap bearing mushrooms the lower surface of 

 the cap is furnished with special organs on whose surfaces the 

 spores are produced. These are in the forms known as gills, 



