THE ASPERGILLUS USTUS GKOUP 



177 



500^ in length, 5.5 to 8.0/x in diameter, approximately uniform in width 

 throughout, thin-walled, smooth, tan to light brown in color, often slightly 



D 



Fig. 50. Aspergillus granulosus; NRRL No. 1932. A, Portion of colony on hay 

 infusion agar showing clusters of conidial structures and small masses of hiille cells, 

 two weeks old, incubation at room temperature, X 1.5. B, Portion of marginal area 

 of two colonies on malt extract agar showing characteristic granular appearance 

 resulting from numerous small clusters of hiille cells, X 1.5. C, Silhouettes 

 of conidial heads, X 48. D, Conidial head showing slightly elongate vesicle, sterig- 

 mata in two series, and constriction in conidiophore just beneath the vesicle, X 750. 

 E, Small clusters, or "granules", of hiille cells, X 48. F, Double cluster of hiille 

 cells, much enlarged, X 265. (Reprinted from Raper and Thorn, "New Species of 

 Aspergilli from Soil," Mycologia 36: Nov .-Dec. 1944.) 



constricted just beneath the vesicle (figs. 47 B and 50 D). Vesicle ovate 

 to elliptical, thin-walled and easily broken, largely covered by sterigmata, 

 12 to 18^ m diameter by 15 to 25/z in length. Sterigmata in two series, 



