34 
The autopsy findings were not frank. At most some 
swelling of the spleen and a little pale thickening of 
the intestinal wall constituted the picture. Smears from 
intestine and nasal mucosa showed no protozoa. The 
blood taken from the living sick ducks showed no parasites 
or anemic changes in either raw or variously stained 
preparations. From the spinal cords of three ducks Dr. 
Fox prepared a 50 per cent, glycerine emulsion which 
was injected into the cerebral substance and abdomen 
of domestic ducks with negative results. A variety of 
different bacterial cultures was obtained from the liver, 
spleen, blood and congested nasal mucosa of several 
birds dead with the disease and injected into domestic 
ducks, but again without reproduction of paralysis. 
Histological sections were cut from the important 
organs of thirteen birds. The kidneys, lungs and 
pancreas showed no abnormalities. The heart muscle 
in some cases and also some of the skeletal muscles 
showed Zenker's hyaline degenerations together with 
minor hemorrhages and oedema. Several of the proven- 
tricles showed low grade inflammatory signs toward 
the gizzard. The intestines regularly showed lymph- 
atic infiltrations of the villi most marked toward the 
tips, but without congestion. The lumen showed no 
parasites, bacterial or protozoal. Liver showed, in al- 
most every case, pigmentation by hemosiderin at times 
as heavy as that seen in progressive pernicious anemia. 
The finer bile ducts here showed peripheral round cell 
infiltrate, which was not continued into the major ducts, 
as determined by serial sections. Parenchymal cells were 
cloudy and swollen. Spleen showed, in early cases 
polymorphonuclear infiltrate of the follicles, in later cases 
atrophy of follicular splenocytes and more or less pigment 
occurred in both stages. The spinal cord and various 
peripheral nerves showed no inflammation or degenera- 
tion as determined by the appropriate special nerve stains. 
The above clinical, histological, protozoological and 
bacteriological examinations having failed to detect the 
