1912 ENTOMOLOGICAL SOCIETY. 75 



have a habit of flying before thunder storms, no matter which way the wind is 

 blowing; but as soon as the rain commences they alight and it is then that occas- 

 ionally a wonderful sight is seen. Thousands congregate upon a bush and open 

 and shut their wings so much in unison that one moment the trees look green, the 

 next reddish. Such a sight was seen by my brother Stuart last year in August, 

 and I have twice observed a somewhat similar scene. No one seems to have made 

 notes upon the migratory movements of these butterflies, though it would be well 

 worth while to do so, and thus get an insight into the daily rate of travel. So 

 far as first arrivals are concerned, these of course depend largely upon the weather 

 or prevailing winds. I have two records of the first noted, June 10th, 1910, and 

 May 16, 1911, while my latest are September 7, 1910 and September 20, 1911. 



Anather butterfly that migrates regularly is the painted lady, Pyrameis 

 cardui. I have known them to come up from the south by hundreds with a hot 

 southerly wind in June, while in other seasons they have been almost entirely 

 lacking, due, at least in part, to unfavourable breezes. These are, so far as I know, 

 the only regular migrants who go south to escape our winter and return to breed 

 like birds, but the numbers that move from place to place as a means of distribu- 

 tion are almost endless. Occasionally there will be a general movement when all 

 kinds including butterflies of several species such as C olios, Pontia, Anosia, Pyra- 

 meis, etc., also dragon flies, embracing several types, are all flying together as if 

 having a single object in view. These flights, however, occur but rarely. 



Moths also migrate, although as they usually fly at night their movements 

 are overlooked, unless they appear suddenly in a district, as did the Snow-white 

 Linden Moth at Ottawa in 1908. 



Beetles nearly all have their restless moods, which occur at any time during the 

 summer months, but their more regular movements are in spring and fall, when 

 they appear to be returning from winter quarters or in search of them. Here also 

 we have the day fliers and night fliers, but, strange to relate, those beetles that are 

 generally most constant in their habits of only coming out in the sunshine will 

 suddenly change them and appear on the darkest nights to fly long distances. 

 Thus we have diurnal denizens such as tiger-beetles and lady-birds flying in com- 

 pany with hosts of other beetles, bugs, stone-flies, caddis-flies, lace-winged flies, 

 tree-crickets, mosquitoes and many more. These have all been collected around 

 lights. Of course some are regular night fliers, especially those commonly called 

 water-beetles. 



Presumably the reason why day beetles sometimes fly at night is the greater 

 protection darkness affords them from birds. During the present year there was a 

 remarkable flight of a small native beetle kno^^^l as the willow leaf beetle, Galeru- 

 cella decora, a very destructive insect. These beetles suddenly appeared in 

 swarms soon after the trees came into leaf. Where they came from is unknown 

 to me, though their flight seemed to be from an easterly direction. They appeared 

 in millions, and soon turned many of the aspen poplars a dirty brown colour by 

 skeletonizing the leaves. The willows likewise suffered, eventually more so, as 

 they are the natural food plant. Judging from the fact that the beetles came 

 suddenly and did not attack the intervening trees, we might suppose that they 

 had been flying at a considerable height, especially as they seemed exceedingly 

 hungry when they came to earth as if from a long journey. It is not an imcom- 

 mon event, however, for willow leaf-beetles to migrate. Other Chrysomelidae do 

 the same thing, though seldom in such large numbers. 



A great inanv insects un{|uestionably fl.y in search of food. The potato-beetle 

 is an example of this, and several others can readily be called to mind, but the 



