224 



POISONING. 



USTILAGINACE.E (SMUT FAMILY). 



Ustilago maydis. — The black powdery fungus known as corn smut is 

 common throughout the corn-producing districts of the central United 

 States, and is occasionally reported as being fatal to stock. Experiments 

 made in Wisconsin and elsewhere show that it is not a very active poison 

 when eaten in moderate quantity. When given in gradually increasing 

 amounts up to 2 lbs., no effect was noted, but 4 lbs. on each of two 

 successive days caused the sudden death of one cow. Since corn smut 



Fig. 74. — Fly anianita {Annuiita Duiscaria). a, Mature plant; h, top view of cap 

 showing corky, patches — both one-lialf natural size. 



has l)een shown to be less fatal when wet, it seems probable that its 

 physical and not its chemical character may be responsible for the death 

 of cattle which have eaten it in considerable quantity. 



POISONING BY SMUT OF BARLEY. 



Causes. The presence of smut in straw, in millers' grains, or in 

 damaged kiln-dried grains which have fraudulently been added to grain 



