NOT DESCRIBED IN PREVIOUS SECTIONS. 567 



Pathogenesis. From 0.25 to 1 cubic centimetre of a bouillon culture 

 injected into the pleural cavity of a rabbit caused a development of all of 

 the symptoms of influenza (Brustseuche) viz., elevation of temperature at 

 the end of five or six hours, cough, nasal discharge, dyspnoea, and death 

 usually in from three to five days. The autopsy showed a distinct pleuro- 

 pneumoiiia and a general blood infection by the bacillus in question. 

 Injections into the circulation also give rise to the symptoms of influenza, 

 including pneumonia, and to death at the end of from ten to fourteen days. 

 Subcutaneous injections resulted in the development of an abscess and of ex- 

 tensive necrosis of the tissues, but did not cause a general blood infection. 

 Guinea-pigs were somewhat less susceptible than rabbits, but injections into 

 tlie pleural cavity produced similar symptoms and death at a later date. 

 White mice and house mice, as a result of intraperitoneal injections, died 

 within two or three days from general blood infection. 



BACILLUS PISCICIDUS (Fischel and Enoch). 



Obtained by Fischel and Enoch (1892) from an infected carp. 



Morphology. Bacilli solitary or in chains of four to five elements, 1.2 

 to 3 /i long and 0.25 ^ thick. Stains by the usual aniline colors and by 

 Gram's method. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 motile, liquefying bacillus. Forms spores. In gelatin plates forms round 

 colonies of a pale yellowish-brown color, having a slightly toothed border 

 and a granular surface. At the end of twenty-four hours a narrow zone of 

 liquefaction can be discerned around the colonies, and at the end of about 

 ten days the gelatin is entirely liquefied. In gelatin stab cultures a scanty 

 growth is seen along the line of inoculation at the end of twelve hours ; the 

 growth upon the surface is rapid, and liquefaction commences at the end of 

 twenty-four hours. Upon agar, at 37 C. at the end of eighteen hours, a thin 

 granular layer is seen, which consists of small, pale-gray colonies. In agar 

 stick cultures a scanty growth occurs along the line of puncture, which does 

 not increase after thirty-six hours. Upon the surface the growth is abundant, 

 forming, at the end of five days a tolerably thick grayish-white layer. No 



frowth occurs upon potato at the room temperature, but at 37 C. a tolera- 

 ly thick, sticky layer of a grayish- white color is developed in three or four 

 days. In bouillon, at 37 C., the medium is clouded at the end of twelve 

 hours, and a thin pellicle is seen upon the surface at the end of thirty-six 

 hours ; this falls to the bottom when the tube is slightly agitated. At the 

 end of four days development has ceased, and the bouillon is again transpar- 

 ent, while a flocculent deposit is seen at the bottom of the tube. The bouillon 

 gives off a penetrating odor, like that of burnt milk. The same odor is given 

 off from cultures in milk, which is peptonized by the action of the bacillus. 

 At the end of twenty days, at 37 C. , the entire contents of the tube have be- 

 come transparent. 



Pathogenesis. Produces a fatal infectious disease in fish ("gold carp") 

 when inoculated beneath the skin ; also pathogenic for mice and for guinea- 

 pigs. 



BACILLUS PYOGENES FILIFORMIS (Flexner). 



Obtained by Flexner (1895) from the interior of the uterus and from an 

 exudate in the pericardial and pleural cavities, of a rabbit which died on the 

 fifth day after parturition. 



Morphology. Pleomorphous cocci-like forms, short or long bacilli, and 

 long threads are seen in cover slips prepared from the exudate. "Very few 

 of the bacilli stain regularly ; for the most part brightly stained spots appear 

 between stained areas. An outer membrane always stains, enclosing the 



