FusARiA OF Potatoes 249 



Average of the above measurements: 

 Conidia: 0-septate, 0.5 per cent, 9 x 4/i 

 1-septate, 3 per cent, 17 x B/j, 

 2-septate, 1 per cent 

 3-septate, 63 per cent, 44.4 x 5.03/i 

 4-septate, 32 per cent, 51.9 x 5.27/x 

 5-septate, 0.5 per cent, 58.5 x 5.7 /x 



55. Fusarium Martii Ap. et Wr. var. minus n. var. (Fig. 44, j to l; 

 PL 1, figs. 3 and 4; PI. vi, fig. 6) 



Differs from F. Martii and F. Martii var. viride by having smaller, 3- 

 septate, conidia, 36.7x4.8 (30-44x4.55-5.1)^1, usually prominent de- 

 velopment of plectenchymic, wartlike stromata, and fewer and larger 

 sporodochia (PI. vi, fig. 6). 



Color of substratum, on potato agar rich in glucose, from light gray to 

 drab and dark olive-buff, with a fuscous-colored spot at the point of 

 inoculation (PI. i, figs. 3 and 4). 



Hab. On rotted tubers of Solayium tuberosum, evidently following 

 Phytophthora infestans, Dutchess County, New York. 



Measurements of conidia on different media are as follows: 



On potato tuber plug, culture seventy-one days old: 



(1) Conidia from a sporodochium 

 Conidia: 0-septate, 8 per cent 



1-septate, 13 per cent 

 2-septate, 29 per cent 

 3-septate, 50 per cent, 30 x*4.6 (26-33 x 3.6-4.8) /x 



(2) Conidia from pseudopionnotes 

 Conidia: 1-septate, 9 per cent 



2-septate, 37 per cent 



3-septate, 54 per cent, 30 x 4.55 (27-34 x 3.9-4.8)^ 



(3) Conidia from oldest part of pseudopionnotes 

 Conidia: 3-septate,' 100 per cent, 37 x4.7 (27^3 x 4.2-5)m 



On slightly acidified hard potato agar, culture eleven days old; conidia 



from pseudopionnotes: 



Conidia: 3-septate, 67 per cent, 43.75 x 4.6 (24-52 x 3.5-5.3)/* 

 4-septate, 28 per cent, 48.65 x 5 (43-53 x 4.3-5.3) /x 

 5-septate, 5 per cent, 52.85 x 5 (50-57 x 4.3-5.3) m 



