118 ESSENTIALS OF BACTERIOLOGY. 



Potato. No apparent growth. 



Bouillon. At 37 C. clouds are formed in the bouillon, which 

 then sink to the bottom, and long chains of cocci found in this 

 growth. 



Staining. Easily colored with the ordinary stains. Gram's 

 method is also applicable. 



Pathogenesis. Inoculated subcutaneously in the ear of a 

 rabbit, an erysipelatous condition develops in a few days, 

 rapidly spreading from point of infection. 



In man, inoculations have been made to produce an eft'ect 

 upon carcinomatous growths. Erysipelas was always produced 

 thereby. When it occurs upon the valves of the heart, endo- 

 carditis results. Puerperal fever is caused by the microbe in- 

 fecting the endometrium, the Streptococcus puerperalis of Frankel 

 being the same germ. 



In scarlatina, variola, yellow fever, cerebro-spinal meningitis, 

 and many similar diseases, the microbe has been an almost con- 

 stant attendant. 



In erysipelas the cocci reside in the lymphatic glands and 

 ducts. They have not been found in the blood. In air, soil, and 

 putrefying matters they have been often discovered. 



Staphylococcus Pyogenes Aurens. (Boscnbach.) 



Origin. Found very commonly in pus (80 per cent, of all sup- 

 purations), in air, water, and earth ; also in sputum of healthy 

 persons. 



FIG. 63. 



1. (48 hours.) Colonies of micrococcus pyogenes aureus. 2. (5 days.) 



Form. Micrococci in clusters like bunched grapes, hence the 

 name staphylo, which means grape. They never form chains. 

 Spores have not been found, though the cocci are very resistant. 



