Fusaria of Potatoes 



255 



The average size and occurrence of septation type of conidia on various 

 media are as follows: 

 Conidia: 0-septate, 5.5 per cent, 10.7 x 3.15/z 



1-septate, 13.5 per cent, 20 x 4.5^ 



2-septate, 17 per cent, 25 x 4.5^ 



3-septate, 60.5 per cent, 30 x 5.41 /z 



4-septate, 3.5 per cent, 34.5 x 5.5/x 



5-septate, rare, 42.25 x 5.85/* 



59. Fusarium striatum n. sp. (Figs. lc 2 and 46; PI. I, fig. 2) 

 Microconidia, at least on aerial mycelium, always present. Macro- 



conidia of shape and septation intermediate between F. Martii and F. 



Solani, mostly 3-septate, 34.7x4.6 (31-36 x 4.4-5) /x, from colorless to 



Fig. 46. — Fusarium striatum, a, Pseudopionnotal conidia from 17-days-old culture on 

 slightly acidified hard potato agar; b, pseudopionnotal conidia from 58-days-old culture on oats; 

 c, conidia from small sporodochium from 32-days-old culture on hard lima-bean agar; d, sporo- 

 dochial conidia from 86-days-old culture on red raspberry cane plug; e, pseudopioyinotal conidia 

 from 13-days-old potato tuber plug (some of them anastomosing); f, pseudopionnotal conidia 

 from 1 2-days-old culture on hard lima-bean agar; g, terminal chlamydospores produced by conidia 

 from 64-days-old culture on hard lima-bean agar with 2 per cent glucose; h, chlamydospores 

 from 32-days-old culture on hard lima-bean agar; i, compound conidiophore from 3^-days-old 

 culture on hard lima-bean agar 



yellowish glaucous and pale turquoise green, in numerous minute sporo- 

 dochia; sporodochia often converging into a pseudopionnotes; aerial 

 mycelium short (rarely up to 3 millimeters high), typically (on various 

 agars) fine, uniformly from loose to very loose, downy in appearance, 

 from white to grayish white; substratum, on agars rich in glucose, from 

 pale glaucous green to tawny olive and sepia. 



Hab. On tubers of Solarium tuberosum., Colorado. 



Latin description.— Microconidiis — saltern in aerio mycelio — semper 

 praesentibus; macroconidiis forma et septatione inter F. Martii et F. 



