1909] The Ottawa Naturalist. 145 



the insects in a state of nature, living, in their environment, 

 their manner and hours of flight, their preference for certain 

 foods, their attitude when at rest, and, by no means least in 

 importance, their dates of appearance, are all valuable points 

 to be observed and noted in the forming of specific associations. 

 Long series should be studied, and, bearing all the above points in 

 view, the variation noted, every capture of each successive season 

 examined for fresh phases of variation and specimens sought 

 for at all time to fill in apparent gaps in the varietal gradient. 

 Aim should also be made, not only at uniting dissimilar, but divid- 

 ing similar forms. For, as already pointed out, neither does 

 dissimilarity always indicate distinctness, nor resemblance uniting 

 of species. Though the most expert will not always succeed in 

 thus successfully associating every specimen that comes to hand, 

 it is astonishing how familiar one having a good eye may become 

 in time with the general facies of different but confusinglv 

 variable species. It may happen that he has grouped several 

 forms as probable varieties for years. i\t last, either by accident, 

 by personal observation, or by having differences pointed out bv 

 another person, characters considered specific are noticed, 

 separation of the series made, and though difficulties may occur 

 for a while, in course of time, with more familiarity with the 

 distinguishing points and extent of variation in the different 

 series, the differences may seem so obvious to his eye that he 

 will wonder how he could ever have confused them. This may 

 truly be called becoming familiar with a species in one locality. 

 Yet an attempt to point out differences in two very similar 

 forms or they may be very dissimilar to his own eye, ^to 

 another man, however good a judgment or wide an experience 

 he may possess, in such a way as to equally convince him of 

 two species, especially by the submission to him of a few odd 

 specimens only, may fail completely, owing to the lack in that 

 other man of familiarity with the species, or with its form in 

 that locality at anv rate. The eye of the latter man is not ac- 

 customed to the slight, and possibly to the former, indefinable 

 differences, which to him may seem, if noticeable at all, varietal. 

 Too much reliance should not be placed upon the opinion 

 given upon local forms by experts not actually familiar with 

 the form in that particular locality. "Professor Brown called a 

 specimen I sent him by this name, and he has a wide experience, 

 and is generally accepted as the leading authoritA" on this group.'. 

 Precisely! But unfortunatelv Prof. Brown does not happen to 

 be familiar with the form as it occurs in that locality, and is 

 uqite likely to have been misled into entirely wrong associations 

 by the specimen, or it may have been the few odd specimens 

 submitted to him. Dr. Jones is after all just as much of a 



