214 
TODD AND WOLBACH. 
are usually occasional and few in number; sometimes, how- 
ever, the disease occurs repeatedly on the same farm, or it 
may become almost an epizootic and carry off at once the 
majority of the horses from a farm, or from the outfit of a 
contractor engaged in railroad construction work. 
Altliough equine diseases which resembled Swamp Fever 
had been noticed previously. Swamp Fever seems to have 
been first recognized as a distinct disease in or about 1880,^ 
and since then it has been widely identified. It has been 
shown to exist in many of the Western States, and several 
attempts have been made to determine its nature. 
The object of the present communication is to review what 
is known of it and to record the results of the study of two 
cases of the disease. The first part of this paper is, conse- 
quently, almost wholly a compilation from the reports which 
are mentioned in the list of references; the latter part states 
the results of our own observations. 
II. Nomenclature. — Names mentioned in the literature, 
which are sometimes applied to Swamp Fever, are : Amer- 
ican surra, malarial fever or typhoid fever of horses, unknown 
disease, no-name disease, plains* paralysis, pernicious anemia. 
III. History and distribution. — The first definite mention 
of Swamp Fever in the literature records its presence in 
about 1884 in cases under the care of Dr. Rutherford at 
Portage la Prairie in the Red River Valley. Since then cases 
clinically identical with Swamp Fever have been reported to 
exist as far north as Dauphin and Yorkton and as far west 
as Edmonton. It is not impossible that Swamp Fever may 
have existed unrecognized in many places in the Northwest 
Territory. Several cases are reported to have occurred in 
the early eighties about Prince Albert and at Red Deer. 
In 1888 Commissioner Perry states that he lost forty horses 
out of a troop of one hundred and twenty from Swamp 
Fever at Red Deer. 
More recently diseases diagnosed as Swamp Fever have 
been reported in the United States from Minnesota, Kansas, 
