GASTROMYCETES 



365 



hard. Within the peridium is the gleba (spore-bearing tissue) 

 with sterile tissue interspersed. Usually the gleba is chambered, 

 and basidia are produced in a layer lining the chambers. Sub- 



FiG. 143. Structural features of Geaster. A. The outer peridium splits 

 into pie-shaped segments that remain folded inward during moist weather. 

 B. The outer peridium turns outward on drying, thus exposing the glob- 

 ular inner portion of the fruit body. C. Diagram of structure of fruit 

 body: a, outer layer; b, outer peridium; c, chambered glebal tissue; d, col- 

 umella; e, rhizomorph. D. Hymenial fragments showing basidia that 

 line the chamber wall. E. Basidia and basidiospores. 



jacent to the basidia may be a network of "yeins" (interorlebal 

 tissue) that serve for support and for food conduction. There 

 may also develop a columella (sterile axial tissue), which is the 

 stipe in Lvcoperdon and other genera. 



The basidiospores are not forcibly discharged, as they are 

 among the Hymenomycetes. Wind is the agent of dispersal for 

 most species. In many genera the hymenial tissues (gleba) 



