MISCELLANEOUS INFECTIONS 607 
and without success ; the material was not preserved. In 
two turkeys entirely free of lesions distinctive of black- 
head, cecal nematodes (one heterakis, one unknown) are 
recorded, and in the intestinal wall of another, also free 
from the disease, forms indistinguishable from ameba 
could be discovered. (1) 
The protocol of the Berwick's Swan is interesting 
because the full fledged disease is not known in this bird. 
"While this case is not by any means typical, the chronic 
cecitis and ameba-bearing necroses in the liver stamp it 
as of a kind with the true infection of turkeys. Perhaps 
the resistance offered by the swan effected a modification 
of the disease, preventing the usual necrotizing enteritis 
and turning it into a chronic interstitial variety. 
Berwick's Swan {Cygnus bertvicki). About a month before death 
passed several large clots of blood. Acute catarrhal enteritis, mural 
endocarditis, chronic colitis, chronic nephritis, passive congestion and 
necroses in liver, acute follicular splenitis, edema of lungs, chronic peri- 
carditis, chronic salpingitis, hydrothorax, hydropericardium, hydro- 
peritoneum. Tissues generally are slightly yellow. In serous cavities 
of thorax is about three ounces of clear fluid. Lungs are distended, 
subcrepitant, pale red and gray, highly edematous. The pericardium 
contains about one-half ounce of clear watery fluid. Epicardium is 
glistening, congested, irregularly thickened especially near the blood 
vessels. The heart is contracted, slightly large, pale brown-red muscle. 
On the posterior surface of the right ventricle extending from the auric- 
ular opening to the pulmonaiy valve is an irregularly curved line of 
grouped, recent red vegetative granulations. Valves negative, they and 
chambers competent. Aorta negative except heavily blood stained. 
Liver is slightly large. What of the liver remains undamaged is homo- 
geneous deep purple. Major portion of right lobe badly contused; this 
seems to have been partly antemortem because there is blood staining 
and mottling under capsule. In view of colon finding and history of 
possible injury it is probably the result of degenerations in the liver plus 
slight trauma. There are several small, pale gray, well outlined, homo- 
geneous areas probably necroses in the liver. The spleen is slightly 
large, soft, egg-shape, capsule smooth. Section surface shows bright 
red homogeneous pulp with clearly cut, large follicles. The kidney 
capsule is smooth, surface smooth brown, consistency firm and tough. 
The section surface gives a dull gray-brown appearance, seemingly from 
( 1 ) Those interested in the investigation of the cause of Blackhead 
are referred to the recent literature by Tyzzer and by Smith, in the Jour, 
of Exp. Med. and Jour, of Med. Research, 1918-1922. 
