Fig. 5. Conidial heads; group types. A, Aspergillus candidus group: A. 

 candidus, NRRL Xo. 308, showing characteristic mature heads of different dimen- 

 sions, X 18. B and C, Aspergillus niger group: B, strain NRRL No. 67, showing 

 typical mature heads, X 30; C, A. niger mut. schiemanni, heads typically globose as 

 shown (Photograph by Edward Yuill), X 30. D, Aspergillus wentii group: typical 

 globose heads of A. wentii, NRRL No. 397, X 18. E, Aspergillus flavus-onjzae group: 

 A. flavus, NRRL No. 1957, typical mature heads, X 18. F, Aspergillus ochraceus 

 group: A. ochraceus, NRRL No. 398, typical mature heads splitting into divergent 

 columns of conidia, X 18. 



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