166 



CD. Sherbakoff 



very narrow sickle-shaped conidia of sporodochia, and comparatively 

 broad and longer anguiform; 6- to 9-septate conidia of pseudopionnotal 

 stage often occurring on various agars. 



20. Fusarium biforme n. sp. (Figs, lu and 17; PI. vii, fig. 10) 

 Conidia of two forms: sporodochial conidia more or less uniformly 

 ellipsoid, 3- to 5-septate, 3-septate measuring 39 x 3.3 (36-46 x 2.9-3.6) m, 

 5-septate measuring 51x3.5 (43-60 x 3-4) ju; pseudopionnotal conidia 0- 

 to 9- and even up to 12-septate, sometimes nearly straight or anguiform, 

 5-septate measuring 52 x 4.2yU, 6- to 9-septate measuring 45-84 x 4-5. 8/x; 

 conidia in mass typically salmon-colored; no chlamj^dospores; mj^celium 



Fig. 17. — Fiisarium biforme. a, Conidia {sporodochium 3 millimeters in diameter), b, 

 conidiophore, from 29-days-old culture on hard oat agar; c, conidia from aerial mycelium from 

 71-days-old culture on potato tuber plug; d, semi-pseudopionnotal conidia from H-days-old 

 culture on slightly acidified hard potato agar; E, conidiophores, f, typical conidia, g, largest 

 and most highly septate conidia, from 10-day s-old culture on rice 



well developed, uniform, white in pseudopiomiotal stage and from pink to 

 pomegranate near substratum in sporodochial stage (on hard oat agar) f"^ 

 substratum from brick red to pomegranate (on oat and other agars). 



Hab. On rotted tuber of Solatium tuberosum, together with F. coer- 

 uleum, Wisconsin. 



Differs from F. diversisporum chiefly in color of mycelium and of sub- 

 stratum on hard oat agar and other agars, and in absence of a uniform 

 and typical arthrosporial stage of aerial conidia, although single conidia 

 of that type occur here also. Differs from F. dijfusum by the presence of 

 8- to 12-septate conidia. 



*2 On the same medium F. diversisporum remains from white to clay in color. 



