256 DISEASES OF DOMESTICATED BIRDS 
of respiration. It is noteworthy that the birds often continue to 
eat, up to a few hours before death. The duration of the disease is 
from two to three days. 
Morbid anatomy. The blood is coagulated and dark red in 
color. The mucosa of the duodenum is swollen and diffusely red- 
dened. The liver is either very much congested or fragile and yel- 
lowish in color. In most cases the spleen is without microscopic 
lesions but occasionally there is a hyperemic swelling of that organ. 
Etiology. In smears from the heart blood stained with the com- 
mon anilin dyes there are seen small rods 0.5 micron to 1.5 microns 
long which stain uniformly. In some cases an organism can only 
be found after long search. Bacteria are found very sparingly in 
smears from liver, spleen, and kidneys of fresh carcasses. In car- 
casses which have lain for several hours the bacteria are found in 
larger numbers. That these are not post-mortem invaders is shown 
by the fact that pure cultures of the organism in question may be 
obtained from such material. The organism is Gram positive in 
culture as well as in smears from tissues and is non-motile. It 
grows on all the common culture media at incubator and at room 
temperature but somewhat more slowly under the latter condition. 
The organism thrives best with access to air and less well anaerobi- 
cally. 
After twelve hours on slanted agar at incubator temperature the 
organism forms sharp bordered, distinctly prominent, shiny colonies 
about the size of a poppy seed. These are thickest in the center and 
become uniformly thinner toward the border. By reflected light 
they are grayish white in color. By transmitted light they are 
bright, transparent and have a bluish shimmer. On long standing 
these colonies do not become larger and do not change in appearance. 
Such isolated colonies develop after a light seeding of material such 
as heart blood from a fresh carcass. After rich seeding of material 
and after transfer from a culture a more uniform layer forms, espe- 
cially in the vicinity of the condensation water, which however, by 
close examination is seen to consist of colonies shaped like fine dew 
drops. After about twenty hours, growth ceases. At room tem- 
perature, growth is observed after twenty hours and stops at about 
thirty-six hours. 
The organism grows in a similar manner on four per cent glycer- 
ine agar, one per cent glucose agar, and on blood serum. On the 
latter medium growth appears first after twenty-four hours at in- 
cubator temperature and continues about three days. After this 
