252 AMERICAN LEPIDOPTERA. 



two persons see such series in the same way. What seems 

 a clean association to the student arranging the species and 

 working more or less consciously with a set of leading char- 

 acters in mind, may seem an obvious misfit to another, see-, 

 ing with an unbiased eye or with another set of characters 

 in mind. In the same way, what may seem to one a dis- 

 tinctly separate series, may to the other appear a mere 

 variation. 



There is no doubt that in every collection of our Agrotids 

 and especially in Euxoa, there are mis-identifications and 

 mis-associations, and for much of this confusion I am at least 

 partly responsible. 



When collectors send me for determination one or two 

 examples of a species captured by them, I am often unable 

 to match the specimens exactly in my own material. If the 

 specimens come from a region well collected over, I am apt 

 to associate them with the species they most nearly resemble, 

 as probably variations or slight local races. If the material 

 comes from a region faunally distinct from anything nearly 

 allied, I am apt to suspect a new species. Ordinarily I am 

 more likely to assume a variety or a race than a new species, 

 and hence the accumulation of additional material usually 

 adds to the number of species recognizable in my collection. 

 Much less error would occur if collectors would send a series 

 rather than a specimen or two for determination. 



In Euxoa structural characters so far have been of little 

 assistance. The genitalia in the males are practically alike, 

 or differ in matters of proportion merely, in a manner diffi- 

 cult to define and not convincing when figured. There is 

 some difference in the antennal structure, but that is even 

 more difficult of description in words, and the extent of 

 possible variation has not been determined. 



The advantage of a new eye over an old collection was 

 very well illustrated when Mr. F. H. Wolley Dod, of Millar- 

 ville, Alberta, looked over my material during the early 

 days of 1910. He detected a number of erroneous associa- 

 tions which I had retained and, on the other hand, convinced 

 me that some of my separations were not maintainable. I 



