84 



21. Peronospora polygoni Thiimen. (/'. rum wis Aut. p. p.) 



On Polygonum scandens L., Johnson, 1893 :33 -.—Hamilton. 7 :1907 ; 

 Putnam, 8:1907. 



22. Peronospora potentiixae de Bary. 



On Potentilla monsepalensis L. {F. norcegica L.). Hamilton. 

 7:1907; Putnam, 8:1907. 

 Upper Iowa T^niversity. 

 Fayette, Iowa. 



