268 



THE FUNGI 



spawn. 1 Some species of Boletus are edible, and they, with the 

 morels (Sec. 267) and truffles (Sec. 269), are sold in the Euro- 

 pean markets with edible gill fungi. 



277. The Gastromycetes. This group, in contrast with the 

 Hymenomycetes, includes forms in which the basidia line the 

 Ulterior of chambers, or cavities, in the fructifications and are 

 consequently inclosed until the fructification matures. Here 



are found the puffballs, earth 

 stars, nest fungi, and carrion 

 fungi. 



The puffballs. These are 

 the fructifications (Fig. 239) 

 of an extensive underground 

 saprophytic mycelium, as in 

 the toadstools and mushrooms. 

 The young puff ball has a 

 white flesh made up of hyphse 

 and filled with small irregular 

 cavities lined with the fruiting 

 FIG. 239. Apuffball^coperdon) gurface (hymenium). The 



spores when ripe lie freely as a brown powder in the dried-up 

 fibrous tissue inclosed in an outer parchment-like envelope. 

 The spores may be discharged through a special opening at the 

 top or scattered by the irregular rupture and decay of the puff- 

 ball. Young puffballs are generally edible, and there is one 

 extraordinary species (Lycoperdon giganteum) which grows to 

 be a foot or more hi diameter and is much pmed as a delicacy. 

 The earth stars. The earth stars (Geaster, Fig. 240) are modi- 

 fied forms of puffballs. The envelope is very thick, and the 

 outer portion splits lengthwise into segments which, when wet, 

 curve back from above and raise the fructifications from the 

 ground. In dry weather the segments are usually rolled up 



1 See Duggar, " The Principles of Mushroom Growing and Mushroom 

 Spawn Making," United States Department of Agriculture, Bureau of Plant 

 Industry, Bulletin 85, 1906. 



