244 DISEASES OF DOMESTICATED BIRDS 
The cells frequently lie in pairs, so that they appear like diplococci. 
The organism is always found in great numbers in the heart blood, 
the pericardial fluid and in the fibrinous exudate. It is stained 
readily by the common anilin dyes, and best by carbol fuchsin. The 
organism is Gram negative, non-motile and does not form spores. 
Indol production is not observed except perhaps in traces in old 
cultures. 
Frosch and Birnbaum succeeded in growing the organism at first 
only on medium containing hemoglobin. The first generation out 
of the goose grew on plain agar and bouillon when plenty of blood 
was carried over to the medium in making the inoculation. Pigeon 
blood agar induced growth but after many transfers failed. A 
medium rich in hemoglobin made as follows was more successful. 
Defibrinated horse blood is mixed with equal parts of distilled 
water to cause the liberation of the hemoglobin. About 1 cc. of 
this solution is added to each tube of melted, cooled agar. The 
agar is then shaken and is subjected to fractional sterilization at 
70° C. for three days. On hemoglobin agar so prepared, the organ- 
isms form a luxuriant grayish white growth. In smears from such 
cultures the rods appear somewhat larger than in smears from the 
animal body and very frequently long thread-like forms are ob- 
served. 
On common agar of slightly alkaline reaction it forms in 24 to 
36 hours a luxuriant grayish white, transparent, slightly opalescent 
layer, which in older cultures becomes brownish yellow in color. 
The condensation water contains considerable sediment. The 
optimum growth temperature is 37° to 38° C. No growth occurs on 
acid agar. 
The period of life of a culture is limited. By holding at room 
temperature, transfers succeeded at 14 days, but many transfers 
fail sooner. The cultures in the incubator nearly all die within 8 
days. 
A slight uniform clouding occurs in bouillon, which after some 
days contains a limited amount of sediment which on twisting, forms 
a spiral column. In some cultures a pellicle is formed of thread- 
like growth. 
In gelatin stab cultures held at 21° C., a slight non-characteristic 
growth is observed in the vicinity of the line of inoculation, and on 
the surface. After some time a funnel-shaped area of liquefaction 
forms slowly, and complete liquefaction eventually occurs. Growth 
on gelatin plates is accompanied by liquefaction and offers no char- 
acteristic features. 
