RAY FUNGUS 



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threads radially situated. Through the periphery and extending 

 beyond are other unclubbed threads, while scattered throughout 

 the colony and beyond it, and in the threads, may be seen many 

 spore-like bodies. The threads and spores stain by Gram's 

 method while the clubs do not. Basic stains also color all the 

 elements. The spores do not stain like bacterial endo-spores. 



Vital Requirements. It is a facultative anaerobe, and grows 

 best in the absence of air, at 37C. Resists drying for a long time, 

 and its thermal death-point is 8oC. after fifteen minutes' exposure. 



FIG. 69. Actinomyces. (Williams.) 



Chemical Activities. Slowly liquefies gelatine, does not curdle 

 milk; and produces a mouldy odor. No gas or acids are formed, 

 nor is H 2 S developed. 



Habitat. It has been found in straw and hay, but never in a 

 healthy body. 



Cultures. On gelatine plates it produces yellowish-gray colo- 

 nies that are very small. These grow into the gelatine, slowly 

 liquefying it. The colonies are very tough and fibrous. In agar 

 tubes it grows very slowly, the first growth being like dewdrops; 

 later these enlarge, turning yellow, and finally brown. The cul- 



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