274. THE AMERICAN NATURALIST. [VoL. XXXV. 
GEOGRAPHICAL DISTRIBUTION. 
Mate. FEMALE. MALE. | FEMALE. 
PONE a 16 13 Montana 4 3 
British Columbia. . I o evada à 2 o 
Tonma o oa 15 21 New Mexico . o I 
&olomdo- 6.40. >- I 2 Ne or 5 2 
Connecticut .. . . I [o] North Carolina 3 o 
District of Columbia 6 2 North D I o 
PUO . S. n 45 23 nio 3 I 
Georgi 8 6 Ontario [o] I 
Illinois IO 3 Pennsylvania . I I 
Indiana . I o South Carolina . 16 2 
Indian Territory o I Tennessee I I 
Kentucky I o Texas 7 5 
Bé... o I tah o I 
Massachusetts . I 2 Virginia 4 10 
Mexico . 17 16 Wisconsin o I 
Minnesota . I o om : 3 I 
Total | 174 120 
III. METHODS. 
A. General Precautions. 
It is hardly necessary to say that work of this kind should 
be done with material in normal condition. I have made no 
measurements where mutilations existed, and only adult birds 
bearing good evidence of representing their breeding ranges 
have been used. It has been necessary to reject a number of 
skins because of lack of data as to sex. As male and female 
shrikes are essentially alike in color and differ little in size, it 
is not possible to verify the original determinations of sex; 
however, there has been no noticeable confusion in this 
respect. 
No attention has been given to the subspecific distinctions 
appearing on the labels of skins, for I have considered it 
Important to avoid all possibility of bias of opinion which 
attention to previous classification might give. 
