THE SWAMP FEVER OF HORSES. 
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system : Normal with the exception of two cysts filled with clear fluid in 
the left ovary. Alimentary tract : Normal. There are many bots attached 
to the stomach and many Sclerostomum equinum in the intestine. The 
mesenteric lymph glands are enlarged and deeply congested ; the other 
lymph glands are normal. 
(b) Minute appearances. — Heart: Negative. Lung: Moderately in- 
jected only. Spleen : Markedly injected. There is a moderate amount 
of brown pigment in the pulp. Liver : Markedly injected. There is a 
lymphoid and plasma-cell infiltration of the portal canals, which also con- 
tain numerous brown pigment-containing cells. Pancreas : Normal. 
Kidney : Normal except for occasional clusters of green pigment granules 
in cells of convoluted tubules. Rarely the amount of green pigment is 
large, filling all the cells in the cross section of a tubule. Adrenal: 
Normal. Muscle : There are numerous cysts of Sarcosporidium in the 
diaphragm. There are very many large ones in the voluntary muscle 
coat of the esophagus ; in this situation the cysts are more numerous and 
of larger size than in any of the horses (Black Gelding, Horses L and 
and H). Duodenum: Normal, except for curious collections, in the 
submucosa, of cells containing large hyaline drops and bluish-green 
pigment; the latter is possibly iron pigment acted upon by HgS. Bone 
marrow : The marrow of the long bones is fatty and contains no blood- 
forming cells. Lymph glands : One bronchial lymph gland is normal. 
Another shows moderate congestion. Another gland, containing carbon 
pigment, has blood in all of the sinuses and resembles a hemolymph 
gland. It contains many phagocytic cells enclosing pigment, red cor- 
puscles, and lymphoid cells. 
Horse V. (Black). — Weight, 950 pounds; age, 10 -f-. This animal 
was kept under observation for thirteen weeks ; its temperature through- 
out this period remained very regular, between 99^ and 101° F., and its 
pulse rate was about 52. On the 9th of July 450 cubic centimeters of 
blood were transfused into its jugular vein from the Grey Gelding (tem- 
perature steadily normal). Twelve days later the temperature rose to 
103.50 F., and on three occasions during the first and second weeks in 
September it reached 104° F. It is possible that these rises may be par- 
tially accounted for by heavy work ; for the animal has been worked con- 
tinually and the temperature has frequently risen to 102°, or even to 103° F. 
No edemas, petechias, or other gross clinical signs have been observed in 
this animal. It is, nevertheless, becoming steadily thinner although the 
appetite remains good and the pulse rate and temperature are low. Octo- 
ber 12, 1910 : Weight, 940 pounds; pulse, 50. There are no edematous 
areas or other physical signs beyond slight wasting of the muscles. 
November 7, 1910: This animal has been becoming steadily weaker; 
wasting of the adductor muscles of the thighs has been especially marked. 
Two days ago the horse was down and was raised to his feet with diffi- 
culty. To-day he was down again and it was impossible to raise him. 
