736 MINNESOTA BOTANICAL STUDIES. 



15. CYLINDROCOLLA Bon. Handb. 149. 1851. 

 Sporodochium irregularly verruciform, gelatinous, bright- 

 colored; sporophore filiform, multiramose; conidia simple, 

 cylindrical, truncate, acrogenous, hyaline, or bright colored. 



The species of this genus are for the most part conidial 

 stages of Calloria; five species occur in this country. 



16. SPHAERIDIUM Fres. Beitr. Myk. 46. 1852. 



Sporodochium globose, subcarneous, not at all gelatinous, 

 substipitate; sporophore as in Gylindrocolla; conidia elongate - 

 cylindrical, hyaline, borne in simple, or branched chains. 



Conidial stages of Helotieae: two species are reported for the 

 United States. 



Tribe Volutelleae. 



Sporodochium disciform, or pulvinate, sessile, or stipitate, 

 margin, rarely the entire sporophore, ciliate or setulose; spor- 

 ophore simple, or sparingly branched, even obsolete and then, 

 replaced by a stroma, hyaline or fuscous; conidia simple, or 

 septate, single, rarely catenulate, acrogenous, hyaline, or 

 fuscous. 



17. VOLUTELLA Tode. Fung. Meckl. 1: 28; 1790. 



Sporodochium disciform, sessile, or stipitate, ciliate, bright- 

 colored; sporophore typically simple; conidia simple, globose 

 to ellipsoid, hyaline. 



Represented in the United States by 12 species. 



18. VOLUTELLARIA Sacc. Syll. Fung. 4:682. 1884. 



Sporodochium pulvinate, sessile; sporophore obsolete; stroma 

 sub cellular, ciliate; conidia simple, acervulate, ovoid, hyaline. 

 A monotypic genus, as yet found only in this country. 



19. CHAETOSTROMA Corda. Sturm D. C. Fl. 2:122. 1829. 



Sporodochium disciform, margin ciliate or setulose with 

 stout, septate, fuscous hairs distinct from the sporophores; 

 sporophore simple, bacillar; conidia simple, typically single, 

 ovate to fusoid, fuscous. 



A single species of this genus has been reported for the 

 United States. 



