IOWA ACADEMY OP SCIENCE 
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5. Anabaena flos-aquae, Breb. 
6. Anabaena stagnalis, Kg. Both of these Anabaena are found floating on 
the water. In their decomposition they produce pig-pen odors. 
Euphyceae. 
CHLOROPHYCEAE. 
VOLVOCACEAE. 
Pandorina. Common in stagnant pools, especially in barnyards. The water 
is repulsive. Cattle will not drink it unless driven to do so. May be injurious. 
Volvox may be placed in the same category. 
Eumycetes. 
PHYCOMYCETES. 
ZYGOMYCETES. 
Mucoraceae. 
The species of this order are common; among them are: 
7. Mucor mucedo, found on horse manure, and 
8. Rhizopus nigricans, found on decaying organic substances. 
There are two recorded pathogenic species. 
9. Mucor corymbifer and 
10. Mucor rhizopodiformis, but these have not been reported as occurring 
in this state. 
11. Mucor stolonifer. 
Common in state. Probably not pathogenic. 
BASIDIOMYCETES. 
Hemihasidii. 
USTILAGINACEAE. 
12. Ustilago maydis, D. C. Corn smut is supposed to be poisonous to 
cattle, but the evidence is not very conclusive. 
13. Ustilago avenae, (Pers.) Jens. The common loose smut of oats is 
supposed to be injurious in large quantities, the same may be said of other 
smuts occurring upon cereals. Among these are barley smut (Ustilago hordei.), 
(U. nuda,) (U. tritici.) 
14. Ustilago neglecta, Niessl. 
Pigeon Grass smut is thought by many farmers in Iowa to cause poisoning, 
especially abortion. Prof. Power, formerly of the University of Wisconsin, 
found present in this smut a small quantity of ergotine. 
Tilletiaceae. 
15. Tilletia foetens (B. & C.) Trel. 
Stinking smut of wheat is not common in this state, but when it occurs in 
flour it causes bad odors. The spores give to the flour a dark color and make 
it unsalable. 
Eubasidii. 
PROTOBASIDIOMYCETES Melampsoraceae. 
16. Coleosporium solidaginis (Schw.) Thum. 
Parasitic on golden rod and some other plants of the order. Common in 
the state. A number of horses in Black River Falls, Wisconsin, a few years 
