120 A MANUAL OF THE ASPERGILLI 



red colonies, pale blue-green conidial heads, and dark-colored reverse. 

 Within the series, different strains vary in the quantity of conidial heads 

 produced, e.g., NRRL No. 79 regularly produces an abundance of heads, 

 NRRL No. 78 relatively few. 



Strains of this series are not so commonly encountered as are those of 

 the A. repens, A. amstelodami, or A. ruber series. And within the series, 

 strains that conform with the typical species description are relatively less 

 numerous than in these other series. In the present study 14 strains be- 

 longing to the A. chevalieri series have been examined and only 6, or less 

 than half, are wholly representative of the species A. chevalieri. 



The series as a whole seems to be relatively unstable, and certain strains 

 and groups of strains appear transitional between this series and the ^4. 

 repens series on the one hand and the A. amstelodami series on the other. 



Culture NRRL No. 88 received from Baarn as the type of Aspergillus 

 chevalieri var. multiascosporus Nakazawa, Takeda, Okada, and Simo points 

 toward the A. repens series. Its ascospores have smooth walls, as in the 

 typical strains of A. chevalieri, but bear low, erect crests in constrast to 

 the thin, flexuous crests characteristic of this species. Spores lacking crests 

 are occasionally seen and these closely resemble A. repens. The colony 

 upon 20 percent sucrose Czapek agar is definitely of the character of A. 

 chevalieri. Nakazawa and coworkers (1934) separated it from A. chevalieri 

 because of its more floccose habit and its more abundant production of 

 perithecia. The former character is evident in the authors' cultures, but 

 perithecia are not produced more abundantly than in certain strains en- 

 tirely typical of A. chevalieri. 



Another variation from the typical species is seen in culture, NRRL 

 No. 87 received from George Smith as Aspergillus oriolus and attributed 

 to Biourge. The ascospores of this culture (and another that is in the 

 NRRL collection, No. 81) have crests typical of A. chevalieri, but the spore 

 walls are finely roughened over their entire surfaces. This character is 

 suggestive of A. amstelodami, although the roughening of the wall is slight 

 in comparison with that species. The colony upon 20 percent sucrose 

 Czapek agar is essentially like that of typical strains of A. chevalieri but is 

 less red in color and bears fewer conidial heads. Although these cultures 

 can be distinguished from type they are not recognized as warranting sep- 

 aration. 



The roughening of the ascospore wall is further accentuated in a group 

 of four apparently similar strains, which it is believed are truly inter- 

 mediate between A. chevalieri and A. amstelodami. Because their asco- 

 spores bear crests of the A. chevalieri type and hence appear "pulley-form" 

 they are retained in the species. However, because they differ from typical 

 strains in additional particulars, they are considered a new variety, namely 

 Aspergillus chevalieri var. intermedium. 



