MICROCOCCUS INTRACELLULARIS. 301 



with well-defined smooth margins. On plain agar the 

 growth is feeble and uncertain. 



Its growth in bouillon is slow and uncertain. It does 

 not cause clouding of the fluid, but collects at the bottom 

 of the tube as a scanty grayish sediment, that when dis- 

 turbed gives the impression of having a mucoid con- 

 sistency. 



It does not grow on potato and causes no change in 

 litmus-milk. 



It grows only at the temperature of the body, and 

 can be kept growing only by being transplanted to fresh 

 media about every two days, and even then growth 

 often ceases after a comparatively small number of trans- 

 plantations. If from a fresh growing culture a number 

 of tubes be inoculated and kept under favorable condi- 

 tions, it is a common experience to have growth on only 

 a part of them. It is sometimes impossible to obtain 

 a second growth on agar-agar. 



In addition to its presence in the meningeal exuda- 

 tion of epidemic cerebrospinal meningitis, this organism 

 may appear as a secondary invader of the lung, causing 

 more or less extensive pneumonic exudation ; of the 

 joints ; the ear ; the eye ; and the nose and throat. 

 Though rarely, its presence in the circulating blood may 

 sometimes be demonstrated (Gwynn). 



Subcutaneous inoculation with pure cultures has 

 usually no effect. Injections into the great serous cav- 

 ities may or may not result in serofibrinous or fibrino- 

 purulent inflammation, though positive results are often 

 obtained on young guinea pigs weighing about 150 

 grams. Intravenous inoculations are equally unsatis- 

 factory, though the results depend upon the original 

 virulence, the age of the culture and the animal selected. 



