300 



MANUAL OF BACTERIOLOGY. 



grows both at ordinary temperatures and in the incubator. 

 The growth is not rapid. The colonies are fine, dry, 

 elevated, irregular in form, becoming opaque. Bulbous 

 ends upon the threads do not usually appear in cultures. 

 The results of the injection of these cultures into the lower 

 animals are as yet uncertain. 



The disease produced by the ray-fungus is called actino- 

 mycosis. It occurs in cattle chiefly, seldom in swine and 



FIG. 84. 



Actinomyces bovis, smear preparation from a pure culture, stained by 

 Gram's method. (X 1000.) 



horses, and occasionally in man. Infection appears to be 

 carried by grain or particles of vegetable fiber which pene- 

 trate the tissue. The presence of such foreign particles as 

 well as the organism appears to favor infection. The infec- 

 tious material frequently enters through the mouth, espe- 

 cially in the vicinity of the teeth, but it may also occur 

 through the skin or the mucous membranes. It leads to the 



