ORDER LYCOPERDALES 555 



session of a prominent sterile base, and a central ostiole on the endo- 

 peridium, whose whole upper portion soon is more or less caducous. In 

 Trichaster, apart from a subligneous columella there is no sterile base, and 

 the endoperidium has no ostiole and either falls off in pieces or adheres to 

 the exoperidium when the latter dehisces. 



Fig. 185. Lycoperdales. (A) Family Geas- 

 traceae. Astraeus hygrometricus (Pers.) Morg. ; 

 portion of gleba showing partial obliteration 

 of hymenial cavities. (B) Family Tulosto- 

 mataceae. Tulostoma simulans Uoyd; portion 

 of gleba showing basidia with laterally pro- 

 duced spores. (Courtesy, Coker and Couch: 

 The Gasteromycetes of the Eastern United 

 States and Canada, Chapel Hill, Univ. North 

 Carolina Press.) 



Family Tulostomataceae. This family is based upon the genus 

 Tulostoma} These fungi are popularly called the stalked puffballs. The 

 spore fruits of this family originate hypogeously but by the elongation 

 of a basal stalk become epigeous. The commonest genus is Tulosloma with 

 a spherical spore fruit 1 to 3 or 4 cm. in diameter and a slender stalk 

 sometimes 5 or more cm. in length and 2 to 4 mm. thick, often with a 

 small volva remaining at its base. (Fig. 186.) The endoperidium opens by 

 an apical ostiole which may be irregular or which may have a projecting 

 striate margin. The 40 or more species are mostly found in drier regions. 

 In some species the basidia are described as producing four basidiospores 

 laterally instead of apically. Whether this is true for the whole genus 

 or for all other genera of the family is not known. (Fig. 185 B.) The hy- 

 menial cavities in this genus and possibly other genera become obliterated 

 by the growth into them of hyphae bearing the irregularly arranged 

 basidia as in Scleroderma and Sphaeroholus stellatus (not as in Nidulari- 



2 Persoon (1801) used this spelling instead of the more usual Tylostoma and for 

 this reason his spelling must be followed. 



