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A MANUAL OF BACTERIOLOGY 



outside of the hairs, and the fungus is hence termed the 

 Trichopliyton megalosporon ectothrix. 



9 The endothrix form occurs later in childhood, is not so 

 persistent as the Microsporon, and does not attack the 

 nails or beard. Microscopically, the fungus is seen to 

 consist of beaded threads, which are rounded or ovoid 

 spores arranged end to end. The ectothrix form rarely 



FIG. 52. Ringworm in a hair. X 350. 



attacks the scalp, but is responsible for all the tinea sycosis 

 and ringworm of the nails and half the cases of tinea 

 circinata. Suppuration is common in this form. Micro- 

 scopically appearances differ ; generally the spores are 

 arranged in chains, but the sporulation is less regular than 

 in the endothrix. The spores in the endothrix and ectothrix 

 varieties measure 4 /m to 12 JUL in diameter. 



The ringworm fungi can be readily cultivated on all 

 the ordinary media beer- wort agar and beer- wort gelatin 

 being especially favourable. They form whitish fluffy 

 growths with rapid liquefaction of gelatin. In order to 

 obtain cultivations the diseased hairs or stumps are 



