Aveust 16, 1918] 
versity of London attached to the Imperial 
College of Science and Technology. 
Due to the absence of Dean Vaughan in 
war service, a reorganization of the adminis- 
tration staff of the University of Michigan 
Medical School has been necessary. The pres- 
ent officers are as follows: dean, Victor C. 
Vaughan, M.D., LL.D., Colonel, M. C., N. A. 
(absent on leave); assistant dean, Charles W. 
Edmunds, A.B., M.D.; acting secretary, Rollo 
E. McCotter, M.D., and assistant secretary, 
Ethel Bradley Flick. 
Tue following new appointments have been 
made in the various departments of Western 
Reserve University. In Adelbert College, 
Webster Godman Simon, A.M., as instructor 
in mathematics. In the School of Medicine, 
Carl J. Wiggers, M.D., as professor of physiol- 
ogy. The following promotions have been 
made in the Dental School: Harold Newton 
Cole, Ph.D., M.D., assistant professor of der- 
matology and syphilology; Gaius Elijah Har- 
mon, M.D., C.P.H., assistant professor of hy- 
giene and bacteriology (now senior instructor 
in hygiene); Bradley Merrill Patten, A.M., 
Ph.D., assistant professor of sistology and em- 
bryology. 
In the Georgetown University Medical 
School Dr. Clarence R. Dufour, who resigned 
as clinical professor of diseases of eye and ear, 
has been appointed emeritus professor; Dr. 
Isaac S. Stone, professor of gynecology, who 
resigned after twenty-six years of service, has 
been succeeded by Dr. J. Thomas Kelly, and 
Drs. James M. Moser-and John A. Foote have 
been appointed assistant professor of pediat- 
rics. 
Dr. R. O. Cromwett, formerly assistant 
plant pathologist at the experiment station at 
West Raleigh, North Carolina, has been ap- 
pointed extension plant pathologist at the Iowa 
State College of Agriculture and Mechanic 
Arts, at Ames Iowa. 
Dr. Samuet T. Daruine, of the International 
Health Board, has been appointed professor of 
hygiene and director of laboratories in the 
School of Medicine and Surgery in Sao Paulo, 
Brazil. 
SCIENCE 
165 
DISCUSSION AND CORRESPONDENCE 
THE CRITERION OF SUBSPECIFIC INTER- 
GRADATION IN VERTEBRATE ZOOLOGY 
INTERGRADATION is now generally accepted, 
both in codes of nomenclature and in practise, 
as the criterion of zoological subspecies. A 
second means of determining subspecific re- 
lationship, the degree of difference, so strongly 
advocated by Dr. C. Hart Merriam? and others, 
has been found unsatisfactory; still more so 
a third, the natural outgrowth of the latter, 
that of general resemblance, which makes the 
species practically equal to a subgeneric group. 
Dr. Ernst Hartert and a few others have em- 
ployed this last method, but it leads to such 
evident inaccuracies as treating the American 
cedar waxwing, Bombycilla cedrorum, as a sub- 
species of the Bohemian waxwing, Bombycilla 
garrula. 
What constitutes subspecific intergradation, 
however, seems still to be debatable, if the 
diversity of usage among current authors is to 
be taken as evidence. Briefly stated, there are 
three ways in which intergradation takes place: 
(1) By a gradual change over contiguous geo- 
graphic areas; (2) by an abrupt change in an 
intermediate area; and (3) by individual va- 
riation, whether or not the ranges of the two 
forms adjoin. The first of these is the kind 
of intergradation so commonly seen on con- 
tinental areas where one form passes insensibly 
into another in the intermediate territory, and 
is so well-known as not to need illustration. 
The second is much less common and often re- 
sults in the presence at certain localities of 
typical examples of both forms, together with 
all shades of intermediates; but the only ques- 
tion likely to arise in treating a case of this 
kind is the allocation of the individuals which 
occur in such places,—whether they shall be 
treated all as the one form to which they col- 
lectively most approach, or whether the more 
or less typical examples of each shall be re- 
ferred to their respective races. The third 
kind of intergradation, that of individual va- 
riation, is of almost as frequent occurrence as 
1 Scrence, N. S., V., No. 124, May 14, 1897, pp. 
753-758. 
