84 THE CANADIAN ENTOMOLOGIST. 



COLLECTING AT LIGHT. 



I have read with much interest a couple of papers by Mr. Hanham, 

 of Winnipeg, on the capturing of insects "at h'ght." I had adopted 

 this method in the Old Country with much success, and last season in 

 this district, near the head of Lake Manitoba, I employed the same 

 means and secured a goodly number of specimens. There is no doubt 

 that light is most efficacious in securing to the one who makes use of 

 it many insects that would otherwise be only rarely met with, but while 

 engaged in thus making captures one cannot help being struck — a point 

 to which Mr. Hanham alludes — with the effect light has upon many of 

 the Lepidoptera, or rather with the different effects it has upon different 

 individuals. Now, it seems to me that a careful observation on the part 

 of entomologists in this respect might in due time throw fresh " light " 

 on the habits or even structure of the insects observed. IV/iy, I may 

 ask, should light have such a different effect upon insects of the same 

 class ? As there is a reason for everything, so there must be here. A 

 casual observer may note that while light acts upon some individuals as 

 an irresistible attraction, to others it is simply repellant, and in the case 

 of others both these effects are combined. Then, again, some are evi- 

 dently thrown into a kind of stupor under the effect of the glare, and 

 settling down near the attractive force, remain immovable for hours; 

 while yet again others are frantic in their struggles to reach the source 

 of their fascination. This difference of effect, while it points to a 

 dissimilarity of temperament, would seem to indicate a difference of 

 structure, if anywhere, in the eye. Is this known to be a fact ; or, if 

 this be not the case, in what does it consist? It seems to me that here 

 is a wide field for investigation, and it might not be lost labour if, during 

 the coming season, those entomologists who adopt light as a means of 

 capture would, as far as possible, classify the insects taken in regard to 

 the effect the light has upon them. 



I may say that when using light, I place it before a closed window 



on the ground floor, and stand outside, and with a net I am able to 

 capture many insects which do not apparently ever settle on the glass, 

 but simply approach within range of the light and then fly away rapidly 

 at an angle, acting much in the same manner as a comet is said to do in 

 regard to the sun. H. Hutchinson, Kinosota, Manitoba. 



ERRATUM. 



Can. Ent., 1898, p. 15, line 8, for '■' no^ commonly" read ^^ most 

 commonly." 



