BACILLUS FROM AN INFECTIOUS VULVAR DISEASE. 
683 
On December 14, 1899, Dr - Steddom, who also made inves¬ 
tigation of the latter outbreak, furnished me specimens of 
diseased tissue taken from the margins of the ulcers. The 
specimens had been taken from the living animals the preced¬ 
ing day and were in good condition, having been kept at a low 
temperature. On the evening of December 14th I made two 
stab cultures on agar agar, from internal portions of the two 
larger pieces of tissue (about 3X2X1.5 inches), from different 
animals, obtaining pure cultures from each. 
The organism isolated is a bacillus resembling, but some¬ 
what smaller than, Bacillus typhosus. It develops readily at 
room temperature or at 90° F., on agar agar, bouillon, blood 
serum, also on gelatine. 
O11 agar agar it develops a white film which spreads rapidly 
and uniformly over the surface ; a slight growth develops slowly 
along the line of puncture. The surface growth is moist, the 
agar agar apparently slightly liquefied, as indicated by the 
touch of the platinum wire. The bacilli usually lie singly, 
though sometimes forming chains of five or six. Sporulation 
is suspected, but not demonstrated. 
On bouillon it forms a characteristic white film on the sur¬ 
face, clouding the medium within forty-eight hours. Examined 
in hanging drop, the bacillus is seen to be actively motile. The 
length varies from slightly ovoid to twice the width of the ba¬ 
cillus. 
On blood serum a white growth forms which penetrates 
more deeply than on agar agar, and liquefies the medium slowly. 
On nutrient gelatine a cup-shaped depression was formed, 
but if liquefaction occurred vaporization immediately followed, 
for no liquid was visible in the culture tube. 
The organism stains with a watery solution of methylene 
blue or fuchsin, but best results were obtained by use of ZiehPs 
solution, staining one minute. In some of the specimens 
stained, the bacilli showed unstained areas, probably indicating 
spore formation. 
On December 29, 1899, a rabbit was inoculated subcutane- 
