632 MINNESOTA BOTANICAL STUDIES. 
AEcidium pedatatum (ScHw.) nom. nov. 
SYN. : 
1834. Ce@oma (4icidium) pedatatum Scuw. ‘Trans. 
Amer. Phil. Soe. 4: 293,0n0; 2685¢ 
1834. Ceoma (4cidium) sagittatum Scuw. ‘Trans. 
Amer. Phil. Soc. 4: 293, no. 2886. 
1672. <icidium Marie-Wilsont Px. 24th Rep. N. Y. 
Mus. for 1870: 92. 
1874. icidtum Petersi B. & C. Grev. 3: 61. 
EXSICC. ; 
Carleton, Ured. Amer. no. 28. 
Hetercecious, inhabiting species of Vzola, and also of some 
other genus of plants not yet determined. 
O. Spermogonia preceding the zcidia. 
I. cidia hypophyllous, seated on small, pale, circumscribed, un- 
thickened spots; cups usually sub-circinating, small, shallow or short 
cylindrical, white, border narrow, often much split and somewhat re- 
curved; spores subglobose, in part angular from compression, epi- 
spore thin, minutely verrucose, 11 to 18 », averaging 14 yp. 
Throughout the United States east of the Rocky mountains, 
from March to June on the blades of various species of violets, 
and less often on the petioles, pedicels and calyx. Specimens 
have been examined as follows: 
On Viola obliqua Httu. Pennsylvania (Schweznztz), Maine 
(Blake), Indiana (Arthur), Illinois (Seymour, Arthur), 
Iowa (Holway), Kansas (Bartholomew, Carleton). 
On Viola ovata Nutt. New Jersey (4/is). 
On Viola sagittata L. Pennsylvania (Schweznitz), Massa- 
chusetts (Asa Gray). 
On Viola pedata L. Pennsylvania (Schweznztz), Alabama 
(Baker), lowa (Holway). 
On Viola pedatitda Don. Kansas (Kellerman), Iowa 
Flolway). 
On Viola primulefolia L. District of Columbia (Greene), 
Mississippi ( Zvacy). 
On Viola Nuttallii Pursu. Kansas (Bartholomew). 
On Viola striata Arr. North Carolina (Biltmore Herba- 
rium). 
On Viola tricolor L. Kansas (Popenoe). 
The form here described is undoubtedly part of an hetercecious 
species, having the alternate forms possibly upon carices. It 
