174 YEASTS AND MOULDS 



taining spores that become free upon its rupture. Or the 

 hyphse may split into segments, giving off end-pieces as 

 reproducing elements, called conidia, the whole giving the 

 appearance of the hand bones, the phalanges representing 

 the conidia (see Penicillium glaucum). 



These moulds enter by wounds, cracks, or hair follicles, 

 and develop in the superficial layers of the skin. The 

 mechanical irritation set up by their presence is largely 

 responsible for the various diseases they occasion . To be sure, 



FIG. 55. Penicillium glaucum. Gelatin culture. Spread stained with 

 gentian violet. 500 to 1. (From Itzerott and Niemann.) 



they can form enzymes, but of what importance they are in 

 human lesions is not known. The diseases are not highly 

 contagious, but of great tenacity when once well advanced. 

 Infective material comes away in all cases with discharges, 

 and should be burned. Their principal diseases in the human 

 being are as follows : 



Ringworm. Of this there are two varieties ringworm 

 of the skin, Tinea circinata, and ringworm of the hairy 

 portions, Tinea tonsurans or Tinea sycosis. This is due to 

 the Trichophyton of various species, depending upon the size 



