NON-PATHOGENIC MICROCOCCI. 



613 



Morphology. Micrococci, from 0.6 to 0.9 n in diameter, associated in long 

 chains which are made up of cocci in pairs or of oval elements showing 

 commencing transverse division. 



Biological Characters not determined. 



219. STREPTOCOCCUS LIQUEFACIENS (Sternberg). 



Obtained from liver of yellow-fever cadavers, also from contents of in- 

 testine. 



Morphology. Spherical or short oval micrococci, from 0.4 to 0.6 n in 

 diameter, solitary, in pairs, or in short chains. 



Biological Characters. An aerobic and facultative anaerobic, liquefy- 

 ing streptococcus. Grows in the usual culture media at the room tempera- 

 ture. In gelatin stick cultures liquefaction occurs rapidly along the entire- 



FIG. 205. 



FIG. 204. Streptrococcus liquefaciens, from anaerobic culture in nutrient gelatin, x 1,000.. 

 From a photomicrograph. (Sternberg.) 



FIG. 205. Streptococcus liquefaciens ; culture in nutrient gelatin, end of seven days at 22 C. 

 (Sternberg.) 



line of puncture, and by the end of a week the gelatin is completely lique- 

 fied ; it is but slightly opalescent, and a scanty white deposit forms at the 

 bottom of the tube. In agar stick cultures a scanty growth occurs at the 

 point of puncture, and closely crowded colonies are developed along the 

 line of inoculation. Upon potato a thin and limited, dry, white layer is 

 formed along the line of inoculation in four to five days. Not pathogenic 

 for rabbits or guinea-pigs. 



220. MICROCOCCUS TETRAGENUS VERSATILIS (Sternberg). 



Synonym. Micrococcus tetragenus febris flavae (Finlay). 



Obtained by Dr. Finlay, of Havana, from his ' ' mosquito cultures "- 

 from the excrement of mosquitoes which he had allowed to draw blood from 

 yellow-fever patients ; by the writer from cultures from the surface of the 

 body of patients in hospital in Havana, and from the air. 



Morphology. Micrococci, in tetrads, or in irregular groups containing three 

 or more united elements ; varies greatly in the size and grouping of the ele- 

 ments, which are sometimes less than 0.5/< in diameter and may measure 

 1.5 p. This micrococcus would probably be classed as a sarcina by somebac- 



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