GASTEROMYCETES 



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of spores they bear. The spores are often large, dark 

 coloured, and have surface markings, warts, network, etc. 

 The peridium is indehiscent, and its wall not differentiated 

 into layers. 



Most species grow under trees, and several have only 

 been met with in the proximity of certain kinds of trees, 

 suggesting parasitism or the formation of mycorrhiza, as is 

 known to exist between species of Elaphomyces and fir- 

 trees. 



So far as at present known, most abundant in Europe, 

 but their subterranean habitat is against their discovery by 

 the traveller in other countries. 



Sclerodermeae 



Peridium thick, wall not differentiated into layers, de- 

 hiscing by a gradual disintegration at the apex, or by 

 splitting into irregular valves. The spores are small, yet 

 there is no definite arrangement for their dispersion as in 

 the Lycoperdaceae. In Scleroderma the tramal plates dis- 

 appear, but the gleba does not become pulverulent. In 

 Polysaccum the tramal plates are permanent, and form 

 sporangiola. 



Distinguished from Hymenogastereae by the well- 

 defined sterile base of the peridium, which sometimes 

 becomes elongated as a stem. 



Distribution general. 



Nidularieae 



Small fungi, not having the peridium wall splitting 

 into separate layers, although layers are differentiated in 

 Cyathus, The walls of the trama become indurated, and 



