74 



Minnesota Plant Diseases. 



duced in cuts in the mouth made by grass blades when the 

 animal is feeding, and from these points spreads throughout 

 the mouth parts. Inoculation with the nodules results in the 

 typical disease. At times the disease becomes epidemic, prob- 

 ably on account of the prevalence of the fungus in certain food. 

 The same fungus, or one very closely related to it, attacks 

 swine. It is not always confined to the mouth parts. Horses 

 have also been known to suffer from the same disease. In the 

 lungs of rabbits, cats and dogs the spores of green molds may 

 lodge. Under favorable conditions of weak resistance, the 

 spores may germinate and induce inflammation in the sur- 

 rounding parts, causing the formation of tubercular growths in 

 the lung tissues. The disease is known as a mycosis. Such 

 fungus spores injected into the blood of animals may also give 

 rise to mycosis in various organs of the body. The intensity 

 of the disease seems to be proportionate to the number of 

 spores injected or inhaled. This is of course not the cause of 

 ordinary tuberculosis. 



Bread mold allies are reported as responsible for diseases 

 in rabbits. They gain entrance to the intestine with the food 

 and produce diseases of the intestinal tract. When injected 

 into the blood the spores may produce diseased conditions in 

 the kidneys and other organs and even in the bone marrow. 

 Death sometimes results from the attack of these molds. 



An ally of the yeast fungus, and apparently also of the comb 

 scab disease of chickens causes in the throat and mouth parts 

 of young cats and dogs pustules and scabs similar to those 

 produced in throats of children. The fungus is found in the 

 scabs and pustules thus formed. Several other external scab 

 diseases of the skin of animals are produced by these fungi, 

 as are also the bald spots, accompanied by scabs on the exter- 

 nal head and throat parts, often found on cattle and less often 

 on dogs, horses, cats, etc. The latter may be identical with 

 bald spot disease in man. 



Diseases of man. Skin diseases of man, analogous to those 

 of the lower mammals, are caused by fungi. Ring worm and 

 some bald spots are prominent among these. They are caused 

 by fungi perhaps identical with those of lower mammals, at any 

 rate very similar to these in all their characters. 



