MUSHROOMS AND TOADSTOOLS 243 



exoperidium, and in the absence of a sterile base and the fact that the 

 fruit body separates easily from the place of attachment it is distin- 

 guished from Lycoperdon. Because they are readily detached and 



Fig. 97. — Specimen of Geaster fornicatus from Carleton Rea, England. {After Lloyd, 

 J. U., and C. G., Bull. 5, Lloyd Library, June, 1902, Mycological Series No. 2.) 



readily blown about, they are called "tumblers." Catastoma has an 

 outer peridium which splits by a circular Hne of cleavage, so that the 

 upper part is dislodged carrying along with it the inner peridium which 



