Chapter XIII 

 THE ASPERGILLUS FLAVIPES GROUP 



Outstanding Characters 



Conidiophores smooth, in some shade of yellow, with color often confined 



to the outer layer. 

 Heads barrel-form to columnar when well developed, white or slowly 



becoming some shade of vinaceous-buff to avellaneous (Ridgway, 



PL XL). 

 Vesicles subglobose to elliptical. 

 Conidia colorless, smooth, thin-walled. 

 HiiHe cells generally present, helicoid or variously twisted. 



The range of variation presented within the group has led workers with 

 only a few representatives before them to offer names and descriptions for 

 the strains under observation. However, when large numbers of strains 

 are brought together and cultivated upon a considerable range of substrata 

 the continuity of the group as a natural and related series of strains becomes 

 apparent. Further study of this whole group may lead to separation upon 

 lines accounting for certain published descriptions not at present identifi- 

 able. For purposes of the present manual, however, it is believed desirable 

 to broaden the description of Aspergillus flavipes (Bain, and Sart.) Thorn 

 and Church sufficiently to include a closely related series of organisms 

 rather than restrict it to the particular strains studied by Bainier. 



Aspergillus flavipes (Bain, and Sart.) Thorn and Church, 

 The Aspergilli, p. 155. 1926. 



Synonym: S. flavipes Bainier and Sartory (Bui. Soc. Myc. France 27: 

 90-96, PL HI., fig. 1-6. 1911). 



Colonies upon Czapek's solution agar rather slow growing, becoming 3 

 to 5 cm. in diameter in about 10 days; mycelium yellowish, dull buff, com- 

 monly becoming brownish in age; heads pale to dull buff in some strains 

 to avellaneous or even very light cinnamon in others (PL IV F and fig. 

 51 A), submerged mycelium persistently colorless in some strains, develop- 

 ing many shades of yellow, orange, orange-brown to red (Madder-brown 

 of Ridgway, PL XIII) or almost black in reverse of colonies in others; 

 in some strains producing at the surface of the agar closely woven yellow 

 to orange masses of hyphae enmeshing numerous helicoid or variously 

 twisted, thick-walled hiille cells; occasional strains showing dark masses 



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