8 FUNGUS-FLORA. 



thus forming a number of free, closed, hollow bodies or 

 peridiola, the inner surface being lined with basidia. These 

 fungi are popularly known as birds'-nest fungi, the open 

 peridium corresponding to the nest and the peridiola to the 

 eggs. 



In some of the subterranean species the basal portion of 

 the peridial wall is more or less thicker than the remainder, 

 and in the above-ground, species this thickened portion or 

 sterile base is much more highly developed, and, as its name 

 denotes, is sterile, or does not produce basidia and spores. 

 In the species of Lycoperdon, &c., the sterile base is developed 

 downwards as a stem, in other species it grows upwards into 

 the gleba as a more or less cylindrical, compact, sterile, 

 hemispherical, or column-like pillar, called the columella. 



In the sub-family Phalloideae the outer covering or peri- 

 dium is termed the volva, and the hymenium is elevated on 

 a variously-formed receptacle. When the spores are formed 

 the hymenial elements, basidia, &c., deliquesce and form in 

 most species a very strong-smelling, green, semi-liquid, 

 dripping mass, in which the spores are imbedded. This 

 green substance contains a considerable amount of a sac- 

 charine substance, which is greedily sought after by flies, 

 through whose agency the spores are supposed to be dis- 

 persed. In many species the receptacle is brilliantly coloured , 

 thus serving as an additional attraction to their insect 

 visitors. No trace of a capillitium is present. 



GASTEOMYCETES. 



Subterranean, or appearing above-ground when mature ; 

 hymenium concealed within a continuous peridium or volva 

 until the spores are formed. Basidia variable, cylindrical, 

 clavate, or sub-globose ; spores produced laterally (Tulostoma) 

 or at the apex of the basidia, variable in number, often more 

 than four, always continuous ( = one-celled or without septa). 

 Capillitium often present. 



Fam. I. HYMENOGASTREAE. 

 Subterranean. Peridium indehiscent ; capillitium absent. 



