210 C. D. Sherbakoff 



(on aerial mycelium in the form of coarse powder) to dark vinaceous 

 purple; typical variation of spore color shown in Plate ii, figures 5 and 6; 

 sometimes on potato stem plug, from one to a few large sporodochia 

 (2 millimeters in diameter) of a bright orange color produced; substratum 

 from colorless to that of the conidial masses; small bluish black sclerotia 

 (I millimeter in diameter) sometimes produced, and then in great num- 

 bers all over the substratum (on potato tuber plug) ; zonation of colony 

 very faint or none on neutral agars in plate cultures. 



Hab. On soft and dry rotted tubers of Solanum tuberosum, Atlanta, 

 New York. 



Latin description. — Macroconidiis gradatim in apicem attenuatis, pler- 

 umque distincte pedicellatis et aequabiliter curvatis, non ad apicem 

 curvatioribus, typice 3-septatis, 34x4.23 (28-38 x 3.7-4.5) ju, vel etiam 

 2-5-septatis; sporodochiis minutis vel mediocribus (usque ad 2 mm. diam.), 

 saepe in pseudopionnotes vergentibus; aerio mycelio saepe — praecique in 

 agaribus in culturis in patellis factis — absente; conidiis ex albido (in aerio 

 myceho similibus magnis granis pulveris) "dark vinaceous purple" (R); 

 vide typicam spororum coloris variationem, Tab. ii, figg. 5, 6; interdum 

 in tuberibus Solani tuberosi, vel unis vel paucis sporodochiis (2 mm. diam.) 

 nitide "orange" (R); substrato hyalino vel eodem colore quo conidiorum 

 moles; interdum sclerotiis minutis livido-atris (| mm. diam.), tum demum 

 eorundem magnis numeris passim in substrato in tuberibus Solani tuberosi; 

 zonatione coloniae vel maxime indistincta vel nulla in agaribus neutraUbus 

 in culturis in patelhs factis. 



Hab. In mollibus vel aridis putridis tuberibus Solani tuberosi, Atlanta, 

 New York, Amer. bor. 



Measurements of spores on different media are as follows: 



On shghtly acidified hard potato agar, culture twenty-three days old; 



conidia from pseudopionnotes : 



Conidia: 0-septate, 4.5 per cent, 9 x 2.7 (6-14 x 2.5-3) /i 

 1-septate, 1 per cent, 18 x 3.2 (13-22 x 2.6-4) m 

 2-septate, 0.5 per cent, 19.5 x 3.2 (17-23 x 2.7-3. 5) ju • 

 3-septate, 89 per cent, 35.2 x 4.5 (23-38 x 3.5-4.7)^ 

 4-septate, 4.8 per cent, 37.8 x 4.6 (31-40 x 4.3-4.7)m 

 5-^eptate, 0.2 per cent, 45 x 4.7 (38-50 x 4.7) m 



