THE ASPERGILLUS GLAUCUS GROUP 145 



checked against the descriptions in Barnes' paper and obviously represent 

 his isolations. 



In the following list, his designations appear as quotations, followed by 

 our identifications based upon careful cultural study: 



"Flame" variant is A. ruber. 



"Green flame" is A. repens. 



"Blue conidial" is .4. chevalieri var. intermedins. 



"Creamy" is a pale yellowish strain of Yuills' genus Cladosarum. 



"D Brown" is A. uslus. 



"C Yellow" is A. amstelodami. 

 Of these, "C Yellow" (NRRL No. 112) shows the ascosporic pattern and 

 differs little from Barnes' normal strain or the authors' A. amstelodami. 

 "Flame" (NRRL No. 59), "Green flame" (culture discarded), and "Blue 

 conidial" (NRRL No. 85) show ascospores of the glaucus group but differ 

 markedly in pattern. Among large numbers of induced variations, changes 

 in the characters of the ascospore have not been found during this study. 

 "D Brown" (culture discarded) produces no ascospores but develops the 

 hiille cells and conidial heads characteristic of the Aspergillus ustus group. 

 These four forms belong to ubiquitous species quite abundant as con- 

 taminants where plant material is handled. Such contamination is not 

 satisfactorily excluded by the work reported. 



"Creamy" (NRRL No. 143) presents a different problem. The possi- 

 bility that this " Cladosarum" was actually derived from the "normal" A. 

 amstelodami is not excluded. Proliferation of the sterigmata in the head of 

 Aspergilli, especially among the A. glaucus lot, is very common. The 

 branches produced sometimes are found sterile but usually become diminu- 

 tive conidiophores with very small vesicles and groups of sterigmata pro- 

 ducing normal spores. The Yuills' Cladosarum olivaceum (NRRL No. 374) 

 was found as a conspicuous variant or contaminant in their culture of A. 

 niger (1938). The colony, conidiophore, vesicle, primary sterigmata, and 

 initial secondary sterigmata are produced as in A. niger, then instead of 

 chains of conidia with the newest or youngest conidia at the bases of the 

 chains and connected directly with the sterigmata, chains of cells are pro- 

 duced that replicate the sterigmata; occasionally a chain is interrupted by 

 one cell producing a group of new chains, thus acting as a primary sterigma. 

 These chains of cells lengthen not at the base as in Aspergillus but at the 

 distal end. In spite of prolonged search, which shows that the cells toward 

 the outer ends of such chains lose definiteness as sterigmata, the authors 

 cannot confirm the finding of a single terminal conidium on each chain as 

 reported by the Yuills. This morphological picture is repeated by Barnes' 

 "Creamy" strain, which must therefore be interpreted in terms of Yuills' 

 genus. Only the two isolations are known thus far. Their failure to pro- 



