KEY TO THE MORE IMPORTANT GENERA OP GASTEROMYCETEAE 565 



Pileus not perforated like lattice-work. Volva not spiny. Tropics of Old and 

 New World, one species in temperate North America. 



Dichjophora 

 No indusium between pileus and upper portion of stipe. 



Pileus and gleba continuous over the apex of the stipe, leaving no apical 



perforation. Brazil. Aporophallus 



Apex of pileus perforate, rarely covered temporarily by a fragment of the 



volva. Most regions of the world. Phallus 



Apex of the pileus covered by a sort of cap, the receptacle, with many lobes 

 or branches so that at maturity, after the gleba has disappeared, 

 it resembles a wig. Southwestern United States and tropical and 

 temperate South America. Ilajahya 



Family Sclerodermataceae. 



Gleba marked by veins into many distinct regions. Capillitium rudimentary. 

 Gleba breaking up into a powdery mass, the veins remaining or disappearing. 

 Peridium firm, thick. 

 Peridium covered externally by conical spines. The spiny spores borne on 



long sterigmata. East Indies. Caloderma 



Peridium not spiny, thick. 



Spores before maturity surrounded by a coat of hyphae. All over the 



world. Scleroderma 



Spores without hyphal sheath. Europe. Pompholyx 



Gleba breaking up into numerous separate, thin-walled peridioles. Peridium 

 thin, falling to pieces at maturity. Europe, America, Asia, 

 Australasia. Pisolithus 



Gleba not marked by veins, capilhtium well developed. Peridium simple, thin, 

 opening by an apical pore. Spores borne laterally on the basidia. 

 _ Europe. Glischroderma^ 



Family Arachniaceae. 



Single genus. Americas, Africa, Australasia. Arachnion 



Family Nidulariaceae. 



Peridioles without funiculus. 



Spore fruit roundish, without typical epiphragma. All continents. 



Nidularia 

 Spore fruit beaker-formed, with epiphragma. North and South America, 

 Asia, Australasia. Nidula 



Peridioles with funiculus. 



Spore fruit cup-shaped, peridium of one layer, peridioles with a thick white 



tunica. All continents. Crucihidum 



Spore fruit bell- or goblet-shaped, peridium of three layers, tunica of perid- 

 ioles thin, hence their color, black or gray. All continents. 



Cyathus 

 Family Sphaerobolaceae. 



Peridium of three layers, including the apical region. Widely distributed. 



Sphaeroholus 

 Middle layer of peridium lacking in apical region. Europe and North America. 



Nididariopsis 

 Family Lycoperdaceae (including Mesophelliaceae). The little known tropical or 

 African genera, Lycoperdopsis, Lasiosphaera, Hippoperdon, and 

 Bovistoides, are not included in the key. 



3 This genus is put in a separate family, Glischrodermataceae, by Rea (1922) 

 and Fischer (1933). 



