THE ASPERGILLUS OCHRACEUS GROUP 275 



A. Conidia thin-walled, smooth A. ochraceus sub-series glaber 



1. Sclerotia dominating the colony appearance; conidia small, about 3.0m- 



a. Sclerotia abundant, buff to pink or purplish in color in age; heads 



hemispherical to columnar, cream-buff to pale ochraceous 



A . sclerotiorum Huber 



b. Sclerotia abundant, at first gray, quickly becoming black; heads 



globose or radiate; upon onions and other bulbs 



A. alliaceus Thorn and Church 

 (A. uentii group, p. 241) 



2. Sclerotia present but secondary to the crowded, honey-yellow conidial 



heads; conidia smooth A. melleus Yukawa 



B. Conidia with firmer walls, echinulate or barred 



A. ochraceus sub-series echinulata 



1. Conidia elliptical to subglobose. 



a. Conidia 3.5 to 5.0m in long axis; echinulate heads ochraceous, 



radiate, and splitting; sclerotia in type material 



A. ochraceus Wilhelm 



b. Conidia 3.0 to 3.5m, spinulose; sclerotia not found 



A. elegans Gasperini 



c. Conidia up to 6.3m in diameter, rough (Otherwise A . ochraceus) 



S. buturacea Bainier 



2. Conidia globose, echinulate, 7.0 to 8.0m in diameter (Otherwise A. 



ochraceus) A. delacroixii (Sacc.) Thom and Church 



3. Conidia strongly elliptical or pyriform, spinulose, 4.0 to 6.0m by 3.0 to 



4.5 M A. ostianus Wehmer 



III. Conidial heads commonly showing a definite greenish tint, near olive-buff to 

 olivine in color A. sparsus Raper and Thom 



Aspergillus sulphureus (Fres.) Thom and Church, in The Aspergilli, p. 185. 



1926. 



Syn.: S. sulphured Fresenius, in Beitr. zur Mykologie, Heft 3, p. 83, taf. 

 XI, fig. 30-33. 1863. See also Sacc. Sylloge 4: 73. 1886. 



Colonies upon Czapek's solution agar at laboratory temperature, growing 

 rapidly, forming a variously wrinkled to zonate felt, white or tinged with 

 yellow to pink or purplish shades. Conidial heads irregularly produced in 

 most cultures, in pale or sulphur yellor tints, mostly globose, but often split- 

 ting into spore columns in age. Conidiophores with walls firm, rough or 

 pitted, yellow, varying greatly with the strain from very short and sparingly 

 produced to clustered in areas and dominating the culture, or entirely cover- 

 ing the mycelium where sclerotia are absent. Vesicles typically globose and 

 fertile over the whole surface. Radiating primary sterigmata closely 

 packed on the vesicular surface, varying from 8 to 10m by 3 to 5/x to several 

 times larger in some big heads, secondary sterigmata usually uniform, 

 phialiform about 8 to 10m by 2 to 3m- Conidia small, globose or subglobose 

 2 to 3 or 3.5m in long axis, thin-walled, smooth. 



A . sulphureus as described by Fresenius had long conidiophores and yel- 



