MICROCOCCUS MENINGITIDIS 241 



. When the Bacillus pyocyaneus is present the pus or discharge 

 may be blue. Proceed as in 3 and 4. 



(g) If yellow granules, having a rosette-like structure micro- 

 scopically, are present, actinomycosis may be suspected and 

 examined for by the methods given in Chapter XV. 



(h) If thread forms be present, streptothrix or aspergillar infection 

 may be suspected (see Chapters XV and XVII) : if large round or 

 ovoid cells or yeast -like forms, Blastomycetes or Sporotrichon 

 (Chapter XVI). 



(i) If a mixture of organisms be present, agar and gelatin plate 

 cultivations should be prepared and further examined by sub- 

 cultures from the colonies. 



(j) If no organisms can be detected microscopically, proceed as 

 in (3), (7), or (9). In the pus of ordinary abscesses micro-organisms 

 can generally be detected, unless caused by the tubercle or glanders 

 bacillus, the pneumococcus, or the Amoeba coli. In broken-down 

 granulomata, e.g. gummata, if unopened, no organisms may be 

 present. 



(3) Make several cultivations on agar and gelatin (anaerobic if 

 required), and examine microscopically and by subcultures when 

 the growths have developed. 



(4) Make two or three sets of agar and of gelatine plate cultiva- 

 tions. Examine the colonies microscopically and by subcultures. 



(5) Stain two or three of the cover-glass preparations by Gram's 

 method, and counter-stain with Bismarck brown. 



(6) The gonococcus and Diplococcus intracellularis may be identi- 

 fied and distinguished by the methods detailed at pp. 247 and 242. 



(7) Inoculate guinea-pigs or mice subcutaneously and intra- 

 peritoneally with the material. 



(8) Organisms can rarely be detected in the blood by a micro- 

 scopical examination of stained films. Therefore 2-5 c.c. of blood 

 should be withdrawn and cultivated (p. 126). 



(9) If the abscess be probably a tropical abscess of the liver, the 

 pus or scrapings from the wall of the abscess should be examined 

 for the presence of the Amoeba coli. (Chapter XVIII.) 



Micrococcus meningitidis 1 



Weichselbaum in 1887 isolated from cases of epidemic 

 cerebro-spinal meningitis (spotted fever) a coccus which 



1 See Gordon, Rep. Loc. Gov. Board, 1907 (Bibliog.) ; Arkwright, 

 Journ. of Hygiene, vol. vii, 1907, p. 193 ; vol. ix, 1909, p. 104. 



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