MICBOCOCCI PATHOGENIC IN MAN. 197 



evident from what has gone before that the character- 

 istics observable by the microscope or by cultivation are 

 not sufficient, but that experiments on animals must 

 also be made, and in many cases even these are not 

 sufficient for a diagnosis. 



Tn a series of diseases in man streptococci have been found, 

 but we have not been able to decide whether we have to do 

 with specific organisms peculiar to the disease in question, 

 or with one of the forms of streptococci previously mentioned. 

 Thus in 



Endocarditis ulcerosa. The masses of micrococci 

 found in the vessels show for the most part a chain-like 

 arrangement of the cocci ; nevertheless staphylococci 

 may present similar appearances in the tissues, and in 

 one cultivation experiment with the micrococci of endo- 

 carditis only staphylococci grew (Wysokowitsch). Accord- 



Fig. 46. Endocarditis ulcerosa X 700. 

 Section from the cardiac muscle. (After a photograph by Koch.) 



ing to the author's experiments referred to above, it is 

 at all events unnecessary to assume the existence of a 

 specific organism in order to explain the origin of an 

 endocarditis. Further, in many cases of pyaemia and 

 pyaemic metastasis, also in puerperal metritis as well 

 as in cerebrospinal meningitis, streptococci have been 



