HYMENOMYCETES 



357 



mass, the front and lower surface bearing long, crowded, 

 pendulous spines. The highest types of Plydnum have 

 a central stem, and a veil is present in some species. 



There is a marked absence of bright colours, the pre- 

 vailing tints ranging from pallid through buff to brown or 

 dusky. 



Some few species are edible; none are known to be 

 poisonous. 



The spores are colourless or very slightly tinted, and 

 altogether there is an absence of breaks in new directions 

 as compared with other families. Cystidia are not known 

 to be present. 



The simple, resupinate species grow on dead wood ; 

 some of the large dimidiate forms are parasitic on trees ; 

 the central-stemmed species grow on the ground. The 

 home of the family is in the north temperate and subarctic 

 zones ; in fact, so far as is known of their distribution at the 

 present time, it may be said that a greater number of the 

 higher types of Hydnum grow in the forests of Sweden 

 than in all the other parts of the world put together. A 

 few species are known from the tropics. 



Agaricineae 



In the present family the common bond of union is the 

 presence of thin flat plates of tissue called gills or lamellae, 

 over which the hymenium is spread. These gills, in the 

 case of central-stemmed species, radiate from the stem to 

 the margin of the pileus, and in laterally attached forms 

 radiate from the point of attachment of the fungus to its 

 matrix. Shorter secondary and tertiary series of gills are 

 interposed between the primary ones, that reach from the 



