BA S IDIOM YCE TES 



395 



Sub-class 2. — Gasteromycetes. 



The Gasteromycetes very closely resemble the Hymenomycetes in 

 the essential points of the structure of the basids. At all events the 

 agreement is close in this respect between the higher Hymenomycetes 

 with cap and stalk, and the Hymenogastreae, a section of the Gastero- 

 mycetes ; while other subordinate sections, such as the Lycoperdaceae 

 and Phalloideae, diverge from the Hymenogastrese only in minor points, 

 as, it was seen, the lower Hymenomycetes do from the higher forms. 

 The possession of a trama with a hymenial layer on either side of it may 

 be here noted. In the ejjternal conformation, however, of the members 

 of the group, a great variety is displayed, and, but for the existence of 

 numerous intermediate forms, the group would 

 appear to lack coherence in this respect, so great 

 is the range of variation. 



The mycele is very frequently in the form of 

 root-like strands, though there is no constancy 

 in this respect, and the simple filamentous 

 mycele occurs abundantly. The compound 

 ?porophores frequently grow to a great size in 

 some of the sections, but the character which 

 unites the whole is the possession of an invest- 

 ing- membrane, th&peridium, within which, and 

 springing from it, are plates of tissue dividing the 

 interior into chambers where the hymenium is 

 produced. 



At the outset there may be noted the remarkable genus Gautieria 

 (Vitt.), which has no peridium. The peripheral chambers are therefore 

 exposed on the free surface. The peridia of other forms vary consider- 

 ably in thickness and other characters, and a tendency exists towards 

 excessive thickening in the basal region, which develops outwards, 

 forming a stalk in some instances, e.g. Lycoperdon (Tourn.) ; or inwards, 

 in which case either a cushion-like body is produced, e.g. Hymeno- 

 gaster (Vitt.), or a central column, e.g. Phalloideae. The whole cham- 

 bered structure is termed the glebe. 



The HymenogastrE/E may be regarded as an assemblage of the 

 simplest forms of Gasteromycetes, possessing usually the simple structure 

 indicated, but including among its members Gautieria without aperidium, 

 and Secotium (Kze.), a genus with a central column traversing the body 

 of the fungus. These two forms but heighten the resemblance which it 

 has been remarked exists between the Hymenogastreae and the Hymeno- 



FlG. 3?4. — A, Octaviana 

 asterosjterjna Vitt., in sec- 

 tion ( X 5). ( Trom I^uerssen 

 after Tulasne.) 



