HYMENOMYCETES. 



THE HYMENOMYCETES (so called from the hymenium or fruit-bear- 

 ing surface) include most of the larger Fungi. The common 

 Mushroom may be taken as the type, as all the members of the 

 Family bear more or less resemblance to it in organisation and 

 reproduction. The plant consists of the mycelium, the recep- 

 tacle, and the reproductive organs. 



The Mycelium, or body resulting from germination of spores 

 (popularly known as " spawn ") gives rise to a Receptacle upon 

 which the Spores, or reproductive bodies, are produced. In the 

 case of the mushroom e.g., what is popularly known as the fungus, 

 consisting of a stem, pileus, and gills, is only the receptacle. The 

 reproductive bodies are situated on the hymenium, which, in the 

 case of the mushroom, is spread over the gills or plates on the 

 lower surface of the pileus. On the hymenium are produced 

 sporophores (basidia) which bear at the apex, usually in groups of 

 four, either slightly stalked or sessile spores. On germinating the 

 spores give rise to a new mycelium, which in its turn develops the 

 spore-producing part of the plant. The Hymenomycetes vary in 

 their substance, being fleshy, or woody, or gelatinous. They are 

 divided into the following six orders : 



A. HYMENIUM FIGURATE. 



I. Spread over the surface of lamellae or gills = Agaricini. 

 II. Lining the interior of tubes or pores = Polyporei. 

 III. Clothing the surface of spines or protuberances of various 

 forms = Hydnei. 



B. HYMENIUM EVEN. 



IV. Horizontal and mostly on the under surface = Thelephorei. 

 V. Vertical and produced all over the surface = Clavariei. 

 VI. Superior; gelatinous fungi = Tremellini. 



A 



