Williams, Fisher, and Udall: The Spavin Group. 
professional residence of some duration in the Rocky Moun- 
tains, the Mississippi Valley, and in the eastern United States 
extending altogether over a quarter of a century, in which 
it was seen that the malady, almost unknown in one region, 
became a scourge in another part of the country, and between 
the two extremes offered every possible variation; peculiarities 
which called for some deeper and more satisfying explanation 
than accident or traumatism. 
Later he enlisted the collaboration of C. W. Fisher, D. V. M., 
of San Mateo, California, and Professor D. H. Udall, D. V.M., 
of the Veterinary Department of the Ohio State University, - 
who selected this topic for their joint thesis for graduation at 
the New York State Veterinary College, and who, during the 
years from 1899 to 1901, conducted a series of original and 
highly instructive investigations in relation to its pathology, 
in which work they were ably advised by Dr. V. A. Moore. 
Since the presentation of their thesis, Drs. Fisher and Udall 
have had opportunities for further valuable observations. The 
wide geographical separation of the contributors permits the 
presentation of views based upon data obtained in numerous 
locations reaching across the continent from the Atlantic to 
the Pacific, and the subject to be viewed from the standpoint 
of student, practitioner, and teacher. 
The conclusions submitted constitute in general the joint 
views of the three authors. The major part of the thesis of 
Drs. Fisher and Udall is presented as such without essential 
change, for which they assume full responsibility. The respon- 
sibility for other portions is accepted by the senior author. 
The very instructive, though all too few, urinalyses herein 
quoted are the work of Dr. George W. Cavanaugh, Professor 
of Agricultural Chemistry, Cornell University, the samples and 
clinical data having been supplied by the senior author. 
PATHOLOGY. 
This affection or group of affections having been generally 
viewed as the result of a traumatism, the pathology has been 
chiefly studied in the light of separate localized maladies, con- 
sequently each has had its morbid anatomy investigated and 
described separately, each description being a repetition of the 
other varying only in the predominance of this lesion in one, 
