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PUBLIC HEALTH BACTERIOLOGY 



over another, tap it smartly, when spores of the fungus 

 will fall into the other tube and inoculate it. 



At 18 C. growth appears in seven days as fine white 

 downy tufts, which increase in size and throw out rays. 

 The surface of the growth becomes covered with a fine 

 white powdery material. If grown on gelatin, liquefaction 

 takes place in twelve to fifteen days. The microsporon 

 fungus gives a more delicate growth than the megalosporon 

 fungus, and also shows microscopically club-shaped ends 

 to some of the filaments, which are not found in the other. 

 In both forms, spores are found on one side of the threads 

 (like the teeth of a crab) or at ends like a bunch of grapes. 



TABLE OF THE PRINCIPAL RINGWORM FUNGI (Agasse-Lafont). 



Trichophyton tonsurans. This fungus is the cause of 

 30 per cent of the ringworm of the scalp in Paris, and 

 almost all the cases in Germany and Italy. In the east end 

 of London, among the Polish, German, and Russian Jews, 

 it is a common cause. It also is found in ringworm of the 

 body, and at times causes an affection of the beard and the 

 eyebrows, dry in character. Rarely, it affects the nails. 



