208 ESSENTIALS OF BACTERIOLOGY 



it forms satin-like, star-shaped colonies, which slowly liquefy. 

 Under the microscope the form of the fungus is well seen. 



Agar Stroke Culture. The little stars, very nicely seen at first; 

 then the culture becomes covered with them, causing a smeared 

 layer to appear over the whole surface, with a sour odor. 



Properties. The milk is not changed in any special way. It 

 is not pathogenic for man or animals. It is found when the 

 milk begins to sour. 



Oi'dium Albicans (Soor; Thrush Fungus, Langenbeck, 

 1839). Origin. Mucous membrane of the mouth, especially 

 of infants. 



Form. Taken from the surface of the culture, a form like 

 yeasts; but in the deeper layers, mycelia with hyphae occur. 



Growth. Not liquefying; snow-white colonies on gelatin 

 plates. 



Stab-culture. Radiating yellow or white processes spring 

 from the line made by the needle, those near the surface having 

 oval ends. 



Potatoes. The yeast form develops as thick white colonies. 



Bread-mash. Snow-white veil over the surface. 



Pathogenesis. In man the parasitic thrush, or " white 

 mouth," is caused by this fungus. In the white patches the 

 spores and filaments of this microbe can be found. Rabbits 

 receiving an intravenous injection perish in twenty-four to 

 forty-eight hours, the viscera being filled with mycelia. 



Blastomycosis or Oi'dium Mycosis. A skin disease 

 described, in 1894, by Gilchrist, and since then by other 

 writers, is due to a fungus which resembles yeast, and which 

 has been called a blastomyces; but Ophuls and Ricketts term 

 it an o'idium, and the former calls the parasite Oi'dium cocci- 

 dioides. 



Form. The fungus increases by budding, but in culture- 

 media it may resemble a mold or o'idium. 



Pathogenesis. Small abscesses form in wart-like lesions, 

 which extend over large areas of the skin, becoming later 

 on systemic and invading lungs and kidneys; abscesses and 

 nodules form in these organs. 



