130 



THE NATURE BOOK 



SWALLOW-TAIL MOTH, 



when revolving, upon some people, 

 or the similar fascination which 

 water continually rippled by wave- 

 lets exercises. To the moths our 

 artificial lights may appear as 

 rushing or whirling objects of this 

 nature, which first attract their 

 interest, and then, exerting an 

 ever-increasing allurement, at last 

 become irresistible and draw them 

 into the vortex. Just as there 

 are human beings who can coolly 

 face a rapidly whirling wheel, 

 while others must turn from it or 

 lose control of themselves, so it 

 may be that some insects are 

 quite immune to such fascination 

 while others cannot resist it. This 

 fascination which light exerts for 

 moths is sure to be observed by 

 the amateur naturalist, and he 

 will naturally ask the " Why ? " 

 of it. As I have never yet met 

 with any plausible explanation of 

 this phenomenon, I offer the above 

 as a suggestion. 



There is no moth that is more 



likely to be seen visiting the lights 

 than the Swallow-tail, whose stick- 

 like caterpillar and leafy cocoon 

 we have previously considered. In 

 the year 1902 these insects were 

 more than usually abundant, and 

 throughout the month of July of 

 that year the electric arc -lights of 

 the town (Coventry) in which I 

 was living were a sight well worth 

 witnessing. The moths were so 

 abundant as to give the effect of 

 a snowstorm as they fluttered 

 around the lights. The pale prim- 

 rose yellow of their wings appeared 

 white in the electric light, and 

 their gentle, fluttering flight gave 

 the eflect of falling snowflakes ; 

 although, of course, flakes of an 

 unusually large size, for their wings 

 sometimes extend two and a half 

 inches. The Swallow-tail is one of 

 the commonest of moths during 

 July. Each female moth deposits 



CATEKPILLAKS OF THE BLACK AKCHES 

 MOTa 



