358 APPLICATION OF METHODS OF BACTERIOLOGY 



MICROCOCCUS INTRACELLULARIS (WEICHSELBAUM), 

 MIGULA, 1900. 



SYNONYMS: Diplococcus Intracellularis Meningitidis, Weichselbaum, 

 1887; Streptococcus Intracellularis (Weichselbaum), Lehmann and Neu- 

 mann, 1896. 



Of the several organisms mentioned that might be mis- 

 taken for the gonococcus, no one of them is as suggestive 

 and none, per se, so important as that concerned in the 

 causation of epidemic cerebrospinal meningitis. 



This organism, described by Weichselbaum in 1887 under 

 the name "diplococcus intracellularis meningitidis," was 

 found by him in the exudations of the brain and spinal 

 cord in six cases of acute cerebrospinal meningitis. 



As its name implies, it is a diplococcus, practically always 

 seen within the bodies of pus-cells (polymorphonuclear 

 leukocytes) in the exudations characteristic of this disease. 

 It is not seen within the other cells of the morbid process. 

 It stains readily with any of the ordinary aniline dyes, 

 but is decolorized by the method of Gram. It is conspicuous 

 for the irregular way in which it takes up the dye, some 

 cells in a preparation (either from the exudate or from cul- 

 tures) being brightly and intensely colored, others being 

 much less so, or, indeed, often nearly colorless. There is 

 also a marked variation in the size of individual cocci, some 

 being normal, others being apparently swollen. These 

 latter are often pale, with a deeply staining centre, giving 

 the appearance of a coccus surrounded by a capsule; it 

 is not improbable that these are degenerated. The ir- 

 regularities here noted are more common in cultures 

 than in fresh exudates from acute cases, and more common 

 in old than in young cultures, a state of affairs fully explained 



