PATHOGENIC SPIRILLA. 511 



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

 odor. 



157. 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 ~oo. (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 denned 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 spirillum, but lique- 

 faction is more rapid. In gelatin stick cultures 

 . liquefaction occurs all along the line of punc- 



ture, and the spirilla sink to the bottom of the 



FIG i84.-Spiriiiumtyrogenum; liquefied gelatin in the form of a coiled mass, 

 colonies in gelatin plate; a, end while a thin, yellowish layer forms upon the 

 of sixteen hours; b, end of twen- sur f a ce ; complete liquefaction usually occurs in 

 ty-four hours; c, ead of thirty- about two wee ks. Upon the surface of agar a 

 six hours. X 80. (Flugge.) thin5 vel i owish i ayer forms along the impf- 



strich. Upon potato, at a temperature of 37 C., 



a thin, yellow layer is usually developed (not always Eisenberg) ; this 

 contains, as a rule, beautifully formed, long, spiral filaments. 



Pathogenesis. Pathogenic for guinea-pigs when introduced into the 

 stomach by Koch's method ; three out of fifteen animals treated in this way 

 succumbed. 



158. SPIRILLUM METSCHNIKOVI. 



Synonym. Vibrio Metschnikovi (Gameleia). 



Obtained by Gameleia (1888) from the intestinal contents of chickens 

 dying of an infectious disease which prevails in certain parts of Russia dur- 

 ing the summer months, and which in some respects resembles fowl cholera. 

 The experiments of Gameleia show that the spirillum under consideration is 

 the cause of the disease referred to, which he calls gastro-enteritis cholerica. 



Morphology. Curved rods with rounded ends, and spiral filaments; the 

 curved segments are usually somewhat shorter, thicker, and more decidedly 

 curved than the " comma bacillus " of Koch. The size differs very consid- 

 erably in the blood of inoculated pigeons, the diameter being sometimes 

 twice as great as that of the cholera spirillum, and at others about the same. 

 A single, long, undulating flagellum may be seen at one extremity of the 

 spiral filaments or curved rods in properly stained preparations. 



