THE CLASSIFICATION OF BACTERIA 363 



3. Streptothrix Hofmanni (Gruber) Kruse 



Mikromyces Hofmanni Gruber: Archiv f. Hygiene, XVI, 1893, 34. 



Morphology. Branched filaments 1.0 ft thick. Do not produce aerial hyphae. 

 The contents of older filaments become segmented into coccoid gonidia. 

 In animal body, clavate enlargements; also in old, 3 months, bouillon 

 cultures. Aerobic. No growth below 22 C. Optimum temperature, 



37 



No growth on gelatin and potato ; on agar and blood serum a scanty develop- 

 ment. 



Glycerin agar slant. A raised, rugose, dull, grayish white to brownish 

 growth. 



Bouillon. Clear, with a granular sediment, and often with a surface membrane. 

 Grows well in fluid media containing 0.5-3 per cent of sugar with the 

 production of acetic acid and alcohol. 



Pathogenesis. Subcutaneous inoculations of rather large doses into rabbits 

 cause a fibro-purulent inflammation at the point of inoculation, with 

 abscess formation, which remains localized. There appears to be no 

 development of the fungus. 



Habitat. Isolated from the air. 



4. Streptothrix Israeli Kruse 



Flugge, Die Mikroorganismen, 1896, 56. 



Noted by Wolff-Israel : Virchow's Archiv, CXXVI. 



Anaerobic, grow poorly in the presence of air. An absence of branched fila- 

 ments in cultures. In anaerobic (Buchner's method) cultures on agar at 

 37 C, fine, dew-like drops or convex colonies, which generally remain 

 discrete. 



Bouillon. Growth composed of small scaly particles. 



No growth on gelatin. 



Agar slant. Cultures show only rods greatly similar to diphtheria, with but 

 little tendency to form filaments. Egg cultures show typical filaments. 



Pathogenesis. Intraperitoneal inoculations of rabbits and guinea pigs result 

 in (4-7 weeks) the formation on the peritoneal viscera of nodules, varying 

 in size from that of a millet seed to that of a plum, in the smaller of which 

 typical actinomyces kernels are found. These contain branched filaments 

 with clavate ends. 



Habitat. Isolated by Wolff and Israel from two cases of human antinomy- 

 cosis. 



