INTRA CELL ULARIS MENINGITIDIS. 517 



never appears within the nucleus and rarely within 

 other cells (Fig. 67). 



It stains with all the ordinary aniline colors, but best 

 with Loffler's methylene-blue. According to Weich- 

 selbaum, it is decolorized by Gram's solution; Jaeger 

 states that this is not constantly the case. 



FIG. 67. 



Diplococcus intracellularis meningitidis. X 1100 diameters. 



Biological Characters. It does not grow at room-tem- 

 perature, but only in the incubator, and its develop- 

 ment is usually scanty on the surface of agar, but some- 

 times a few colonies grow quite vigorously. It does 

 not grow at all or scarcely any in bouillon, and very 

 scantily in bouillon plus one-third blood-serum. It 

 grows comparatively well on Loffler's blood-serum 

 medium as used for diphtheria cultures. 



When grown on nutrient agar or glycerin-agar, at 

 the end of forty-eight hours in the incubator, there 

 develops a tolerably good growth, appearing as a flat 

 layer of colonies, about one-eighth of an inch in diam- 



