IN SUSCEPTIBLE ANIMALS. 621 
room temperature—better in the incubating oven. Upon gelatin plates, at 
20° C., at the end of twenty-four hours small, angular, transparent scales 
may be seen upon the surface with a low-power lens; at the end of three or 
four days these form flat, more or less irregular, shining, gray colonies, with 
tin and often dentate margins; these colonies may become confluent and 
form adry, scaly layer which by reflected light has a peculiar, fatty lustre 
In gelatin stab cultures the superficial growth is in the form of a trans- 
parent, dry, grayish layer with dentate margins, not more than three to five 
millimetres in diameter. Upon agar, at 36° to 37° C., a thin, whitish-gray, 
dry layer is formed. 
Pathogenesis.—Pathogenic for mice, for guinea-pigs, for linnets, and for 
green-finches; less so for sparrows. Chickens, pigeons, and rabbits, accord- 
ing to Klein, areimmune. Of eight mice inoculated subcutaneously with 
one or two drops of a bouillon culture, six died within forty-eight hours 
and two recovered. Out of eight guinea-pigs inoculated in the same way 
four died in forty-eight hours and two recovered. At the autopsy the 
lungs and liver were found to be hyperemic, the spleen not enlarged. The 
peu? were present in large numbers in blood from the heart and in the 
ungs. 
BACILLUS GALLINARUM. 
Obtained by Klein (1889) from the blood of chickens which succumbed 
to an epidemic disease resembling ‘‘ fowl cholera.” The bacillus is believed 
by Klein not to be identical with Pasteur’s bacillus of fowl cholera, and is 
said not to be pathogenic for rabbits, which would seem to differentiate it 
from this bacillus (Bacillus septicaemize haeemorrhagicz). 
Morphology.—Bacilii with rounded ends, from 0.8 to 2 # long and 
0.3 to 0.4.4 thick; often in pairs. 
Stains with the usual aniline colors. 
Biological Characters.—An aérobic, non-liquefying, non-motile bacillus. 
Does not form spores. Grows in the usual culture media at the room tem- 
perature—better in the incubating oven. Upon gelatin plates forms grayish- 
white, superficial colonies, which later present the appearance of fiat, homo- 
geneous, whitish discs with thin edges and irregular margins, and by 
transmitted light have a brownish color. The deep colonies are smfll and 
spherical, and have a brownish color by transmitted light. In gelatin stab 
cultures a thin, gray layer with irregular margins and of limited extent 
forms upon the surface, and a scanty growth occurs along the line of punc- 
ture in the form of a grayish-white line. Upon the surface of agar, at 
87° C., a thin, gray layer with irregular margins has developed at the end of 
twenty-four hours; later this extends over the entire surface as a thin, gray- 
ish-white layer. No growth occurs upon potato at 37°C. In bouillon, at 37° 
C., development occurs, with clouding of the bouillon, within twenty-four 
hours; later a deposit consisting of bacilli is seen at the bottom of the tube, 
but no film forms upon the surface. 
Pathogenesis. —Chickens inoculated subcutaneously with a pure culture 
die in from twenty-four hours to eight or nine days. Pigeons and rabbits 
are immune. 
BACILLUS CAPSULATUS. 
Obtained by Pfeiffer (1889) from the blood of a guinea-pig which died 
spontaneously. : 
Morphology.—Thick bacilli with rounded ends, usually two or three 
times as long as broad; often united in chains of two or three elements; may 
grow out into homogeneous filaments. Stained preparations show the ba- 
cilli to be enveloped in an oval capsule which may be considerably broader 
than the bacilli themselves—two to five times as broad; where several ba- 
cilli are united they are surrounded by a single capsular envelope. 
Stains with the usual aniline colors, but not by Gram’s method. In pre- 
parations which are deeply stained with hot fuchsin or gentian violet solu- 
