154 C. D. Sherbakoff 



4-septate, 4 per cent 



5-septate, 81 per cent, 50.5 x 4.5 (38-60 x 3.9-4.8)/* 

 6-septate, 4 per cent, 56 x 4.7 (48-64 x 4.4-5.2) /* 

 7-septate, rare, 62 x 5.2/* (only one measured) 



On the same medium as above, culture sixteen days old; conidia from 

 aerial mycelium and indistinct pseudopionnotes: 

 Conidia: 1-septate, 1 per cent, 18 x 3.5/* (only a few measured) 

 2-septate, 1 per cent, 24 x 4/* (only a few measured) 

 3-septate, 12 per cent, 33 x 4 (21-44 x 2.9-4.8)/* 

 4-septate, 6 per cent 



5-septate, 71 per cent, 50 x 4.3 (38-62 x 3.5-4.7)/* 

 6-septate, 7 per cent, 60 x 4.7 (55-64 x 4.5-4.8)/* 

 7-septate, 2 per cent, 62 x 4.7 (59-65 x 4.4-4.8) /* 



Average of the above measurements: 

 Conidia: 1-septate, less than 1 per cent, 18 x 3.5/* 

 2-septate, 2 per cent, 24 x 4.0/* 

 3-septate, 20 per cent, 36 x 4.0/* 

 4-septate, 12 per cent 

 5-septate, 63 per cent, 50 x 4.3/t 

 6- and 7-septate, 3 per cent, 68 x 4.8/* 



F. effusum, especially in its sporodochial stage, much resembles the fol- 

 lowing other species: F. subulatum, F. lucidum, F. bijorme, F. diver- 

 sisporum. From F. subulatum it can be at once distinguished by the diam- 

 eter of the conidia and by the larger size of sporodochia. 40 From F. 

 lucidum it differs primarily by the common presence of 6- and 7-septate 

 conidia, which are absent in F. lucidum, and by denser red substratum than 

 that of the latter species. From F. bijorme it differs mainly by absence 

 of the long, 9- or more septate, conidia in pseudopionnotes, and also by 

 absence of arthrosporial conidial form, the pluriseptate conidia and arthro- 

 sporial conidia on aerial mycelium being more or less common in F. bi- 

 jorme. From F. diversisporum it differs by absence of arthrosporial co- 

 nidia, which are typically produced on aerial mycelium of F. diversisporum. 



40 Sporodochia of F. subulatum as a rule are small, but on whole steamed potato tubers they may be as 

 large as those of F. effusum. 



