598 DISEASE IN WILD MAMMALS AND BIRDS 
all animals which had been in the collection at least three 
months, a period which would seem to exclude the proba- 
bility of an imported infection. Because of the isolated 
character of the cases and impossibility of making a clini- 
cal diagnosis, no attempt at specific nomenclature as used 
in veterinary medicine has been made, hemorrhagic sep- 
ticemia seeming to cover its identity and nature. 
The disease kno^\^l as fowl cholera is practically al- 
ways associated with the bacteriological discovery of a 
member of the hemorrhagic septicemia group while its 
pathology corresponds ^^'ith that of mammalian infection 
with these germs. Enteritis is a prominent feature. This 
disease has appeared thrice among our parrots carrying 
off from six to ten birds before hygienic measures became 
effective. In all three our cultures showed the bipolar 
organisms. Besides these specific outbreaks numerous 
isolated cases of acute general infection have occurred 
among small passerine and picarian birds which could 
not be determined as hemorrhagic septicemia by bacte- 
riological methods although superficially resembling it in 
gross patholog}^ ; they yielded to the same hygienic meas- 
ures. Perhaps we were dealing with fowl plague, a 
disease believed to be due to a filterable virus. That this 
is the case is strongly suggested by an outbreak of fowl 
typhoid in the parrots, from some fatal cases of which 
we were able to isolate B. sangiiinarium, and by a group 
of deaths in small parrots from which no specific organism 
could be recovered. 
The identification of these supposedly specific diseases 
— plague, typhoid, septicemia, leucemia — by pathological 
criteria is by no means simple even if we have at hand the 
complete description of Moore, of Hutyra and Marek, of 
Ellermann and of Ward and Gallagher. Bacteriology 
must decide and cultures should be made upon bodies 
recently dead. In addition to the above infections we have 
had two small outbreaks of psittacosis in parrots from 
which it was possible to isolate the specific organism. On 
