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A MANUAL OF THE ASPERGILLI 



ish-brown to fuscous or fuligineus. Conidiophores arising from submerged 

 hyphae (fig. 47 A) ranging up to 500m long by 3 to 6m, aerially borne conidio- 

 phores, ranging from very short (fig. 47 Ai) up to 125m by 2 to 5m, sinuous, 

 sparsely septate, with walls rather thin, smooth, and uniformly colored 

 some shade of brown. Vesicles hemispherical to subglobose, 8 to 20m in 

 diameter, smaller in some strains (fig. 47 A). Sterigmata colorless or 







Fig. 47. Aspergillus ustus group, X 840. A, Typical conidial head showing com- 

 paratively loose sterigmata in two series and conspicuously roughened conidia, strain 

 NRRL No. 278. A u Diminutive head, as often seen in strain NRRL No. 275. B, 

 Typical head of Aspergillus granulosus, NRRL No. 1932. 



colored, semi-radiate, loosely arranged into two series, primary sterigmata 

 4 to 7m by 3m, secondary sterigmata 5 to 7m by 2.0 to 2.5m- Conidia globose, 

 3.5 to 5.0m, roughened, echinulate to marked with conspicuous color bars, 

 ranging from greenish through olive-gray to yellow-brown or fuligineus. 

 Many strains producing thick-walled hulle cells (fig. 49 E) ranging in form 

 from irregularly ovate or elongate in some strains, to serpentine, helicoid, 

 or twisted in others, essentially as in Aspergillus flavipes. 



