PATHOGENIC SPIRILLA. 



Biological Characters. An aerobic and facultative anaerobic, liquefy- 

 ing, motile spirillum. Spore formation not demonstrated. Grows in the 

 usual culture media at the room temperature. Upon gelatin plates small, 

 white, punctiform colonies are developed at the end of twenty four hours, 

 which under the microscope are seen to be finely granular and yellowish or 

 yellowish-brown in color ; liquefaction of the gelatin around these colonies 

 progresses rapidly, and at the end of forty-eight hours is usually complete in 

 plates where they are numerous. Isolated colonies on the second day form 

 saucer-shaped depressions in the gelatin the size of lentils, having a sharply 

 denned border. In gelatin stab cultures liquefaction progresses much more 

 rapidly than in similar cultures of the cholera spirillum, and a stocking- 

 shaped pouch of liquefied gelatin is already seen on the second day, which 

 rapidly increases in dimensions, so that by the end of a week the gelatin is 

 usually completely liquefied ; upon the surface of the liquefied medium a 

 whitish film is seen. Upon agar a moist, slimy layer, covering the entire 

 surface, is quickly developed. The growth in blood serum is rapid and 

 causes liquefaction of the medium. \Jponpotato this spirillum grows at the 

 room temperature and produces a slimy, grayish-yellow, glistening layer, 

 which soon extends over the entire surface. The cholera spirillum does not 

 grow upon potato at the room temperature. The cultures of the Finkler- 

 . Prior spirillum give off a tolerably strong putrefactive odor, and, according 

 to Buchner, in media containing sujrar an acid reaction is produced as a re- 

 sult of their development. Thy have a greater resistance to desiccation than 

 the cholera spirillum. 



Pathogenesis. Pathogenic for guinea-pigs when injected into the 

 stomach by Koch's method, after previous injection of a solution of car- 

 bonate of soda, but a smaller proportion of the animals die from such injec- 

 tions (Koch). At the autopsy the intestine is pale, and its watery contents, 

 which contain the spirilla in great numbers, have a penetrating, putrefactive 

 odor. 



SPIRILLUM TYROGENUM. 



Synonyms Spirillum of Deneke; Kasespirillen. 



Obtained by Deneke (1885) from old cheese. 



Morphology. Curved rods and long, spiral filaments resembling the 

 spirilla of Asiatic cholera. The diameter of the curved segments is some- 

 what less than that of the cholera spirillum, and the turns in the spiral fila- 

 ments are lower and closer together. The diame- 

 ter of the "commas" is uniform throughout, so 

 that this spirillum more closely resembles the 

 cholera spirillum than does that of Finkler and 

 Prior. 



Stains with the usual aniline colors best 

 with an aqueous solution of fuchsin. 



Biological Characters. An aerobic and fac- 

 ultative anaerobic, liquefying, motile spirillum. ^^ 

 Spore formation not demonstrated. Grows in 



the usual culture media at the room temperature FIG. 183. Spirillum tyroge- 

 more rapidly than the cholera spirillum and num. x TOO. (Flugge.) 

 less so than that of Finkler and Prior. Upon 



gelatin plates small, punctiform colonies are developed, which on the second 

 day are about the size of a pin's head and have a yellowish color; under 

 the microscope they are seen to be coarsely granular, of a yellowish-green 

 color in the centre and paler towards the margins. The outlines of the colo- 

 nies are sharply defined at first, but later, when liquefaction has commenced, 

 the sharp contour is no longer seen. At first liquefaction of the gelatin 

 causes funnel-shaped cavities resembling those formed by the cholera spiril- 

 lum, but liquefaction is more rapid. In gelatin stab cultures liquefaction 

 occurs all along the line of puncture, and the spirilla sink to the bottom of 



