PAPERS OX BIOLOGY AND AGRICULTURE 129 



Ou Viola Rafinesquii Green, Anna, Illinois, April 23, 

 1921. 



Type specimen Xo. 4724, Herbarium Illinois Plant Di- 

 sease Survey. 



Although the host plant occurs over large areas in the 

 region where this disease was collected, the spots are 

 rare and easily overlooked. Where they occur the dead 

 or dying leaves on the lower part of the stem yield 

 abundant pycnidia. 



Ascochyta Rhodotypi n. sp. Spots definite, large, 

 angular and irregular, white with narrow dark red edge ; 

 sometimes involving large areas on the leaf when the 

 red borders are much broader and more irregular. 

 Pycnidia scattered, few, am^Dhigenous 140-180 microns 

 with distinct papillate ostioles. Cells of pycnidial wall 

 large, light brown. Pycnospores hyaline, uniseiDtate, ob- 

 long, ends rounded, slightly constricted at septa, 

 straight, 3-4 x 11-15 microns. 



On leaves of Elwdoiypos Jierrioides University Cam- 

 pus, Urbana, Illinois, Julv 15, 1919 and September 10, 

 1919. 



Type specimen Xo. 4726. Illinois Plant Disease Sur- 

 vey Herbarium. 



Few diseased leaves were found on any bush, but the 

 disease appears each year on the same branches. Three 

 clumps of bushes have been watched and the disease has 

 appeared in a mild form on these three successive sum- 

 mers. 



