424 MINNESOTA BOTANICAL STUDIES. 
mens of these were not left at the University herbarium. No 
species however are reported by him, that have not been col- 
lected by the staff of the survey. Mention of Seymour’s collec- 
tions is appended to each species reported by him. 
The nomenclature of Burrill* has been made use of in the 
list and for full synonymy the reader is referred to the works 
cited below. Britton and Brown’s Illustrated Flora of the 
United States and Canada has been closely followed in the 
naming of all host plants. 
Of the Erysiphez, nineteen species in all have been col- 
lected, distributed among the genera as follows : Spherotheca, 
3; Erystphe, 5; Uncinula, 3; Phyllactinia, 1; Podosphera, 
1; Microsphera, 6. In field work carried on during such a 
long period of time and by as many as ten collectors acting 
independently, it is to be expected that the number of collec- 
tions of common forms will be increased at the expense of the 
number of species. <A glance at the list given below will show 
that such has been the case in Minnesota. There are undoubt- 
edly at least a dozen more species of blights in the state, and 
it is hoped that this list will aid future observations. In citing 
the district of collection, only the county name is given. 
1. Spherotheca humuli (DC.) Burre tu, Bull. Ill. St. Lab. 
Nat: Hist. 2 2’ 400. 1887- 
On leaves of: 
feubus hispidus L.: St. Louis, July, 1886, Holway 46. 
GS. castagnet Lev.) 
Viola sp. indet.: Brown, July, 1891, Sheldon 851. 
flumulus lupulus L.: ——,+ Sheldon 7020. 
2. Spherotheca castagnei Lev. Ann. Sci. Nat. III. 25: 139. 
FOS; 
On leaves of: 
Taraxacum taraxacum (L.) Karst.; St. Louis (?); July, 
1886, Holway 276. (Not published in Arthur’s report.) 
* Burrill, T. J., and Earle, F.S. Parasitic Fungi of Illinois. Bull. Ill. St. 
Lab. Nat. Hist. 2. 1887. 
Ellis, J. B., and Everhart, B.M. North American Pyrenomycetes, 2-30. 
1892. 
+ Mr. Sheldon’s last field note book has not, up to the present time, been 
found. Consequently the dates of collection, the district and the name of the 
host plant often cannot be determined. The missing data are indicated as 
above. 
