634 MINNESOTA BOTANICAL STUDIES. 



Exsicc. : 



Jaczewski, Komarov, Tranzschel, Fungi Ross. no. i6 m . 



Ellis and Everhart, N. Am. Fungi, nos. 254 In , 1007 T , 

 241 1 m . 



Seymour and Earle, Econ. Fungi, no. 456 m . 



Thueman, Myc. Univ., no. 430 J . 



Linhart, Fungi Hung., no. 33 T . 



Krieger, Fungi Sax., nos. no 1 , in HI , 472 n , 561 1 , 562 u , 

 1006 1 . 



Rabenhorst, Fungi Europ., no. 2I94 1 . 



Sydow, Mycotheca Marchica, no. 468 m . 



Sydow, Ured. Exsicc., nos. 33 m , 82 I , 117", 286", 335 x , 

 378", 640 J , 935 l , 1136 m , 1184 J , 1229 J . 



Shear, N. Y. Fungi, no. 321 m . 



Vize, Fungi Brit., no. 77 x , ii2 m . 

 Autaecious, inhabiting species of Viola. 



0. Spermogonia preceding or accompanying the aecidia, amphi- 

 genous, punctate, honey yellow ; spores elliptical or nearly globose, 3 

 to 5 fi broad by 4 to 6.5 /j. long. 



1. yEcidia hypophyllous and also on petioles, pedicels and calyx, 

 substratum moderately thickened, in indefinite and irregular clusters, 

 often covering nearly the whole leaf, especially noticeable on the veins 

 and stalks, crowded ; cups broad and low, rather coarsely lacerate and 

 irregularly recurved; spores subglobose, somewhat angular from com- 

 pression, minutely verrucose, 14 to i8// broad by 15 to 22 ;j. long (Eu- 

 ropean) or 16 to 2O/J. broad by 18 to 26 /JL long (American) ; wall thin. 



II. Uredo chiefly hypophyllous; sori at first in small groups on dis- 

 colored spots, later sparsely and indefinitely scattered, soon naked, 

 cinnamon brown, pulverulent ; spores subglobose, echinulate, 17 to 

 28^1 in diameter, brownish yellow; wall varying from thin to thick; 

 pores four, equatorial. 



III. Teleutosori hypophyllous, indefinitely scattered, round, small, 

 soon naked, pulverulent, chocolate brown ; spores brown, usually 

 broadly elliptical, less often oblong-ovoid or irregular, slightly or not 

 at all constricted at the septum, smooth, or finely tuberculate especially 

 on the upper half, 15 to 23, a broad by 21 to 30 ,u long (European), or 

 16 to 26 11. broad by 28 to 44/>- long (American) ; apex obtuse, some- 

 what thickened, with a pale and broad apicuous, while a similar pro- 

 jection often occurs on one side of the lower cell near the septum ; 

 pedicel hyaline, fragile, not as long as the spore, somewhat deciduous. 



Throughout North America, occurring upon nearly every indi- 

 genous species of Viola. Spermogonia and ascidia from April to 



