64 BACTERIOLOGY 



Potato. No growth. 



Pathogenesis. For pathogenesis see various text-boolcs. 



Habitat. Pulmonary exudate in croupous pneumonia; frequently associated 



with bronchopneumonia, peri- and endocarditis, pleuritis, meningitis, 



otitis-media, etc. Also in saliva of healthy man. 



17. Str. Weichselbaumii (Trev.) L. and N. 



Diplococcus intracellularis-meningitidis Weichselbaum : Fortschritte d. Medizin, 



1887, No. 18. 

 Neisseria Weichselbaumii Trevisan : Gen., 1889, 32. 

 Streptococcus intracellularis-meningitidis Lehmann-Neumann : Bak. Diag., 1896. 



Morphology. Cocci in twos, with a capsule. Stain by Gram's method. 

 Blood serum. In 48 hours colonies 2-3 mm., round, flat, convex, colorless, 



moist, glistening ; becoming confluent. 

 Agar slant. Growth round flat grayish translucent colonies. 

 Bouillon. Slightly turbid ; a whitish sediment. 

 Potato. A scanty growth, or invisible. 

 Litmus milk. Unchanged. 

 In gelatin. Only feeble growth ; no liquefaction. 

 Pathogenesis. Mice and guinea pigs only feebly or doubtfully affected. 

 Habitat. In meningeal exudate in an epidemic of cerebrospinal meningitis. 



Variety. — Streptococcus of Bonome Sternberg: Manual of Bacteriology, 



1892, 325. 

 Not suiiSciently described to distinguish from the above, except that it does 



not grow on blood serum, and is more pathogenic to mice and rabbits. 

 Habitat. Obtained by Bonome from the exudations in the cerebrospinal 



meninges in cerebrospinal meningitis. 



18. Str. sanguinis Pitfield 



Sir. sanguinis-canis Pitfield: Queen's Microscopic Bulletin, Philadelphia, 1897, 44. 



Morphology. Cocci actively motile, usually occur singly, but occasionally in 

 pairs. On agar or in bouillon they form long chains. Stain by Gram's 

 method. Flagella were not stained, but were seen occasionally. Growth 

 on media white. 



Pathogenesis. Pathogenic to guinea pigs and rabbits. In dogs a local abscess. 



Habitat. Found in blood of dogs, in healthy and diseased animals. 



