S66 



THE BASIDIOMYCETES 



undergo autodigestion, and only the powdery spore mass re- 

 mains, at times interspersed with stiff, thick-walled threads, the 

 capillitium, which functions in spore dissemination. In the 

 Phallales the spore mass becomes slimy. In Sphaerobolus the 

 entire gleba is discharged intact by a special mechanism. In the 

 Nidulariales the masses of glebal tissues (peridioles) serve as dis- 

 seminules. 



The peridium is variable in structure. In Gautieria it is 

 ephemeral and disappears early in the development of fructifica- 

 tions. As the opposite extreme, it is thick and firm in Sclero- 



FiG. 144. T^'pes of capillitium among puff balls. A. Capillitium of Bovlsta. 

 B. Capillitium of Lycoperdon. C. Capillitium of Mycenastrum. 



derma, rupturing irregularly and tardily in S. geaster to permit 

 escape of the spores. The peridium is differentiated into layers 

 in Geaster, the exoperidium everting to become a stalk, and the 

 endoperidium becoming perforate by a special mouth for the 

 escape of the powdery spores. The inner peridial layers in 

 Sphaerobolus evert to project the glebal mass forcibly while it is 

 still partly enclosed by the outer peridial layers. 



Little success has attended efforts to grow Gastromycetes in 

 artificial culture. The basidiospores are refractory to germina- 

 tion. Conidia have been reported for a few species only. All 

 are saprophilic, although some species have been found to asso- 

 ciate themselves with trees in a mycorrhizal relationship. 



For the present purpose the Gastromycetes are divided into 6 

 orders, following the arrangement of Fischer (1933): Hymeno- 

 gastrales, Podaxales, Sclerodermatales, Lycoperdales, Phallales, 

 and Nidulariales. The general treatises of Alassee (1901), Hol- 

 los (1904), and Coker and Couch (1928) should be consulted 

 for the taxonomy of the Gastromycetes as a whole. For special 

 genera the studies of Zeller and Dodge (1918, 1918a, 1919, 1924, 



