ACTINOMYCES MADURA 227 



which is not yet fully understood. The description given is 

 generally applicable only slight variations being noted. 



Vital Requirements. It is a facultative aerobe. The thermal 

 death-point for the spores is 85C. for three minutes, and 75C. 

 for five minutes. Vegetative thread forms die at 6oC. Grows 

 best at 37C., and scantily at room temperature. 



FIG. 70. Streptothrix hominis. (Kolle and Wassermann.) 



Cultures. Generates upon all culture media. In Bouillon. It 

 appears in little clumps which cling to the glass, but eventually 

 sink to the bottom in masses. In Gelatine. It grows sparingly 

 in clumps, slowly liquefying the medium. Upon Agar. It forms 

 shiny round colonies, that are first devoid of color. They resem- 

 ble an umbilicated vaccine vesicle and adhere tightly to the agar. 

 In Milk. It grows without coagulating the medium. On 

 Potato. The culture is very slow, and without chromogenesis. 

 Old colonies are powdery, due to spores. 



Pathogenesis. In man it produces madura foot, an affection 

 characterized by induration, ulceration, and fistulas formation 

 with pus. 



