604 PATHOGENIC SPIRILLA. 
the liquefied gelatin in the form of a coiled mass, while a thin, yeflowish 
layer forms upon the surface; complete liquefaction usually occurs in 
about two weeks. Upon the surface of agar a thin, yellowish layer forms 
a b c 
Fig. 184.—Spirillum tyrogenum; colonies in gelatin plate; a,end of sixteen hours; b, end of 
twenty-four hours; c, end of thirty-six hours. Xx 80. (Fliigge.) 
along the impfstrich. Upon potato, at a temperature of 37° C., a thin, yel- 
low layer is usually developed (not always—Hisenberg) ; 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. 
SPIRILLUM METSCHNIKOVI. 
Synonym.—Vibrio Metschnikovi (Gameléia). 
Obtained by Gameléia (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 re- 
sembles fowl cholera. The experiments of Gameléia 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 spi- 
ral 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 spiril- 
lum, and at others about the same. A single, long, undu- 
lating flagellum may be seen at one extremity of the spiral 
filaments or curved rods in properly stained preparations. 
Stains with the usual aniline colors, but not by Gram’s 
method. 
Biological Characters.—An aérobic (facultative an- 
aérobic?), liquefying, mvtile spirillum. According to 
Gamaléia, endogenous spores are formed by this spirillum ; 
but Pfeiffer does not confirm this observation, and it must 
be considered extremely doubtful in view of the slight 
resistance to heat—killed in five minutes by a temperature 
ee 50° | ae in me usual Rossa media at the room 
epi, temperature. Upon gelatin plates small, white, puncti- 
ringer ris A mee form colonies are developed at the end of inalee to SiX- 
culture in nutrient t€€0 hours; these rapidly increase in size and cause lique- 
gelnditi,eudartorty: faction of the gelatin, which is, however, munch more rapid 
eight hours. From a with some than with others. At the end of three days 
photograph. (Fran- large, saucer-like areas of liquefaction may be seen resem- 
kel and Pfeiffer.) bling that produced by the Finkler-Prior spirillum and the 
contents of which are turbid, while other colonies have 
produced small, funnel-shaped cavities filled with transparent, tiquefied gel- 
atin and resembling colonies of the cholera spirillum of the same age. Under 
