On Trichophyton tonsurans (the Fungus of Ringworm), 237 



Experiments. 



1. With the following solution: — 



Sod ee Phosph 1 grm. 



Amnion. Tart 10 „ 



Aquae distill , . . 1,000 cub. centims., 



which I found had been in use in cultivation experiments at the Brown 

 Institution. 



Thirteen cells with ringworm hairs in contact with this solution 

 were placed at different times in the incubator, viz., two for three 

 days, three for four days, five for six days, two for nine days, and one 

 for fourteen days. There was no growth of trichophyton in any of 

 them. 



Some minute particles of bread, on which common mould had been 

 sprinkled, were placed in a drop of the same fluid in a cell,, and placed 

 in the incubator. Long mycelial threads grew on the under surface 

 of the cover-glass. 



Again, a piece of bread slightly mouldy at some points was soaked 

 in the same fluid, and with ringworm hairs placed on it, was put into 

 a bottle, and the bottle placed in the incubator. The roots of the 

 hairs were found entwined with a rich mycelial growth of fungi, 

 considerably larger than the fungus of ringworm, but the spores of 

 trichophyton could be seen after preparation and maceration in 

 potash to be undeveloped. 



2. A fluid (known, I believe, as Cohn's fluid) with the following ; 

 composition : — 



Magnesium Sulphate . . . 1 grm. 



Potassium Nitrate 1 grm.. 



Calcium Phosphate 0*2 grm. 



Distilled Water 500 cub. centims. 



One per cent, ammonium tartrate to be added before use. 



Two cells c barged with ringworm hairs and the above fluid were 

 placed at different times in the incubator, one for two and the other 

 for eight days. The fungus grew in neither. Two hairs containing 

 spores were floated on the surface of the fluid in a test-glass, and 

 placed in the incubator for four days. There was no growth. Other 

 ringworm hairs, placed in a small tube, were sunk at the bottom of 

 the same test-glass. There was again no growth. 



Ringworm hairs were placed on bread soaked in the fluid, the bread 

 being then put in a bottle and placed in the incubator for four 

 days. The hairs were found enveloped in aspergillus. Trichophyton 

 spores had not grown; being found after maceration to be in the 

 same condition as in a diseased hair freshly extracted from a ringworm 

 patch. 



