606 DISEASE IN WILD MAMMALS AND BIRDS 
much more considerable extent, at least in gross bulk, 
than in the former. Changes in the liver secondary to 
enteric disease from bacterial infection take the form of 
cholangitis, thrombosis, degenerations and probably 
cirrhosis while abscesses and necroses succeed upon pro- 
tozoal or metazoal parasitic involvement. The latter is 
exemplified by amebic abscess in man and other mam- 
mals and by ''blackhead" and "quail disease" in birds; 
it is to the latter conditions that attention is now directed. 
The chapter upon the cause of these diseases has yet to 
be completed, although many reams have been written 
about it, while the transmission is fairly well understood 
and the pathology well described. My purpose here is to 
discuss our experience with the two above mentioned 
diseases which, while far from conclusive, may assist 
somewhat in explaining their etiology. There is also 
reproduced our original report upon quail disease from 
the Society's Report of 1915, giving data and figures. 
Blackliead has been found in five wild turkeys. An 
unusual case in a Bermck's Swan is recorded since it 
bears a striking resemblance to the disease. 
The points at issue in the determination of the etiology 
of blackliead are the importance of Heterakis papillosa 
in the ceca and the frequency and activity of ameba or 
histomonas. In three of the five cases of the disease in 
turkeys the nematode was found macroscopically in 
the ceca, in two it was not; in one its absence 
was confirmed microscopically. In two of the turkey 
cases, forms corresponding to the ameba or histomonas 
were discovered w^liile the descriptions of the he- 
patic lesions in two birds use the term coccidia which, 
from a revision of the slides, is probably incorrect 
although some of the parasites seem to be possessed of a 
doubly contoured refractile margin. The larger, more 
diffuse and ameba-like forms in the intestinal wall sug- 
gest that the hepatic inclusions belong to the same group. 
In only one case was exhaustive search made for coccidia. 
