DISEASES CAUSED BY MOLDS, ETC 101 



The protoplasm contains vacuoles and one or more 

 nuclei. The manner of reproduction is characteristic; 

 the capsule protrudes and forms a bud and contains a 

 part of the protoplasm and a half of the nucleus. It 

 gradually grows larger, and is eventually pinched off 

 to become another cell. The cells frequently contain 

 spores, which are liberated when the cell disintegrates. 

 The most important property of yeasts is the fer- 

 mentation of sugars whereby the sugar is changed 

 into ethyl alcohol and carbon dioxide. Commercially 

 the yeasts are used in a variety of ways, but chiefly 

 in the manufacture of beers and wines. Few of the 

 yeasts are infectious for man, and but one will be 

 mentioned. 



BLASTOMYCOSIS. 



This infectious disease is caused by a yeast called 

 the blastomyces. In appearance it corresponds to the 

 yeast-cells described above, having a thick cell-wall, 

 with one or more nuclei in the protoplasm, and 

 vacuoles. Occasionally it forms threads called mycelia 

 (sing, mycelium). 



The skin is most often affected. Small nodules 

 form, which soften and discharge a yellow pus. They 

 spread slowly and sometimes involve a considerable 

 area of skin. Infection of the lungs is more serious 

 and often leads to pneumonia. A few cases of gen- 

 eral infection have been reported with abscesses in 

 the liver, spleen, and lungs. 



Where the organisms that cause the disease come 



