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A MANUAL OF THE ASPERGILLI 



in short or dwarf races less than 500m long, in other strains ranging up to 

 500 to 1000m or longer, varying from 5m in diameter in dwarf forms to 10 

 to 20m in long-stalked forms, with walls thick, smooth, colorless or slightly 

 yellowed near the vesicle in certain strains in age. Vesicles typically 



Fig. 59. Aspergillus candidus. A, Strain XRRL No. 305 on Czapek's solution 

 agar at room temperature, 10 days. B, Strain NRRL No. 314 on Czapek's solution 

 agar at room temperature, three weeks. Note contrast between compact colony 

 of No. 305, consisting of crowded conidiophores, and loose spreading colony of No. 

 314 in which production of conidial heads is very irregular. C, Strain NRRL No. 

 312, portion of colony showing scattered black sclerotia, X 3. D, Strain NRRL 

 No. 308, conidial heads, X 18. 



globose, ranging from 40m in diameter in very large heads (fig. 60 A), and 

 typically fertile over the whole surface, to small globose heads (fig. 60 B), 

 often very much reduced to support simple groups of sterigmata appearing 

 almost penicillate (fig. 60 D). Sterigmata typically in two series, usually 

 colorless, primary varying greatly in different strains, in different heads of 



