236 SUMMARY OF CURRENT RESEARCHES RELATING TO 



and outside the cells were diplococci resembling Neisser's gonococcus, 

 staining with aniline dyes, but not by Gram's method. Broth cultures 

 were uniformly clouded, and often formed a pellicle ; on ascitic agar after 

 24 hours, greyish-white, translucent shining colonies appeared, having 

 round wavy margins and more opaque centres, which later became 

 yellow and brown, whilst on the margins a characteristic crystalline 

 deposit was noticeable ; on ordinary agar growth was slower, on potato 

 hardly visible ; on sloped agar cultures with neutral red and glucose 

 it took on a pale pink colour, the medium remaining unchanged ; 

 growth was good in milk, but coagulation did not occur ; no growth 

 was obtained on gelatin at 18°-22° C. ; the diplococcus only grew in 

 the presence of oxygen ; indol reaction and Legal-Weil's test were 

 negative ; addition of glycerin to the media inhibited growth. For 

 animals this diplococcus was found to be only slightly pathogenic. 

 Serum from a patient suffering from cerebrospinal meningitis 

 agglutinated the diplococcus — the authors regarding this as a specific 

 reaction. 



Bacterium cyaneum : a New Chromogenic Organising — E. L. 

 Leonard describes a micro-organism that was discovered on several 

 occasions in air plates made in the Hendrix Laboratory during 1900- 

 1901, but has not been again met with. The colonies of this bacterium 

 are remarkable for the deep blue pigment they produce in the sur- 

 rounding medium. It is a non-pathogenic chromogenic bacillus 1 /x- 

 2 • 5 /a in length, • 7 /jl in thickness, longer forms appearing in broth 

 cultures. It is non-motile. It contains refractile deeply staining 

 granules, but no spores, capsule or flagella have been observed ; it stains 

 by the ordinary aniline dyes, and also by Gram's method. Growth is 

 best at room temperature ; it grows well at 37° C, but does not form 

 pigment ; at 10° C. no growth occurs ; it is killed by 5 minutes' ex- 

 posure to moist heat of 68° C. ; no growth occurs under anaerobic 

 conditions. On agar plates at 37° C, 24 hours old, colonies are coarsely 

 granular and greenish-yellow in colour, the older colonies having thin 

 irregular edges ; in those growing at room temperature, many fine, 

 irregular, blue granules occur throughout the central portion of the 

 colony, the surrounding medium being lightly tinged blue. On gelatin 

 plates, 24 hours old, colonies are small, granular, brownish-yellow, with 

 circumscribed edges ; the medium is unchanged, but liquefaction com- 

 mences after 48 hours, and is complete in 3-4 days, the medium 

 becoming slightly greenish-yellow in colour. Litmus milk shows no 

 change within 36 hours ; after 48 hours it becomes more alkaline, and at 

 the 4th-5th day it is decolorised, but remains uncoagulated, the organism 

 forming a blue precipitate at the bottom of the tube. Growth on potato 

 appears only after 3-4 days. On blood serum a yellow-green growth is 

 seen after 24 hours ; it is elevated and moist ; there is a slight blue 

 coloration of the medium, which, after a week, becomes liquefied and of 

 an olive-green colour. Fermentation tests in dextrose-free bouillon 

 show no gas formation, nor is gas produced in any sugar solution. 



t Johns Hopkins Hosp. Bull., xv. (1904) p. 398. 



