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MANUAL OF POISONOUS PLANTS 



is examined microscopically, the spores are found to be abundant in the hair 

 follicle, the fungus causing the hair to drop out. The inflammatory process 

 spreads in the sebaceous glands causing a suppression of the excretion with 

 the formation of crusts anl scab. Occasionally Sarcoptes were found but 

 Drs. Melvin and Mohler do not believe that they were the principal cause of 

 the disease, although when present the animal parasite may aggravate the trouble. 

 All ages and breeds of horses are susceptible as are both sexes. The animal 

 stands around the rubbing posts all day and finally dies. 



Rabbits, dogs, guinea pigs are immune. Experiments with horses were 

 not successful, which these writers think may be because the right stage of the 

 fungus was not used for inoculation experiments. 



Treatment. The authors recommend dynamo oil and sulphur in the propor- 

 tion of one pound of the latter to a gallon of oil. Coal tar sheep dips have also 

 been used. 



Fig. 108. Favus ot mouse (Oospora porriginis) from a culture. 

 A single thread more highly magnified. After Fliigge. 



a. Mycelial threads. 



Oospora, Wallr. 



Fungus with small tufts spreading or pulvinate, mucedinous, loose, or 

 somewhat compact ; fertile hyphae, short, with few branches ; conidia trans- 

 parent, usually in chains, globose or ovoid, hyaline or slightly colored. 

 Oospora porriginis (Mont, and Berk.) Sacc. Achorion Schonleiuii, Reinak. 



Favus, Tinea favosa. Honeycomb Ringworm 



Mycelium flexuose, simple, branched, or forked, continuous conidia, ovoid, 

 triangular or somewhat cubical, varying 3-6 M in diameter; mycelium in masses 

 with granular protoplasm occasionally branched at the end, the ends swollen, 

 club-shaped, branches of the mycelium with lateral branches; spores oval, round 

 or angular, 3-8 M long and 3-4 ^ wide, single or in chains. The threads of 

 the fungus are readily detected in the bulbs and the shafts of hairs when sodium 

 nitrate or potassium hydroxid is added, but at a distance of two inches the 

 fungus cannot be detected. Sections of the nail stained also show threads 



