510 



PATHOGENIC AEROBIC BACILLI 



diameter. Under a low power the recent colonies are seen to be granular, 

 to have a sinuous and sharply defined margin and a pale-brown color which 

 is more intense at the centre and in scattered points upon the surface. When 

 magnified one hundred diameters the surface appears to be coarsely granular, 

 and coarse, irregular spiculae are seen about the margin. In glycerin-agar 

 tubes, at 37. 5 C., growth occurs upon the surface and along the line of 

 puncture as small, white, isolated colonies. Upon blood serum a slightly 

 elevated, white, shining layer is developed. In milk a white deposit is 

 formed at the bottom of the tube and the milk undergoes no apparent change. 

 On potato no visible growth was obtained. 



Pathogenesis. "Inoculations of cultures of the bacillus obtained from 

 two of the cases were made in eight rabbits, two guinea-pigs, and two white 

 mice. All the animals showed marked emaciation, and, with the exception 

 ot two rabbits, all the animals experimented upon died in from ten to twenty- 

 nine days. The inoculated bacillus was obtained from the heart's blood of 

 two of the rabbits that died." 



Fia. 159. FlO. 160. 



FIG. 159. Bacillus gracilis cadaveris, from a gelatin culture. X 1,000. From a photomicro- 

 graph. (Sternberg.) 



FIG. 160. Bacillus gracilis; colonies in gelatin roll tube, end of forty-eight hours. X 12. From 

 a, photograph. (Sternberg ) 



159. BACILLUS GRACILIS CADAYERIS (Sternberg). 



Obtained (1889) from a fragment of liver, of man, kept for forty-eight 

 hours in an antiseptic wrapping. 



Morphology. Bacilli about 1 // broad and 2 ft long, associated in long 

 chains. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 motile, non-liquefying bacillus. Spore formation not observed. In gelatin 

 roll-tubes the deep colonies are opaque and spherical ; superficial colonies 

 circular or slightly irregular in outline, white in color, and opaque or slightly 

 translucent. In gelatin stick cultures, at 22 C., at the end of fiv<> days a 

 rather thick, white mass at tho point of puncture, covering one-third of tin- 

 sin-face, and closely crowded, opaque colonies at bottom of line of puncturr. 

 with slander, branching outgrow! li above. In nutrient agar, at the end of 

 five days at 22 C., a milk-white growth upon the surface and opaque 

 growth to bottom of line of puncture. On potato, at end of five days at 

 22 C., rather thick, cream-white growth witn irregular margins along the 

 impfstrich. Cultures in bouillon have a milky opacity and a very disagree- 

 able odor. Grows in agna coco without formation of <ras. 



Pathogenic for rabbits when injected into the cavity of the abdomen. 



