THE CANADIAN ENTOMOLOGIST. 95 



them thriving. The water should be reasonably clean. Three things 

 should be carefully observed. (i) There must be a surface up which 

 they can climb to transform : if the sides of the kit are too smooth put 

 in some sticks ; (2) there must be room enough between the netting 

 cover and the water for complete expansion of their wings ; (3) they 

 must remain out of doors where the sunshine will reach them. This last 

 point especially is essential to success. But there is still an easier way to 

 do it, and one which, when a species is very common, will prove entirely 

 satisfactory. The several nymphal stages (excepting the youngest, not 

 likely to be collected) are very much alike. I am in the habit of preserv- 

 ing the younger nymphs and putting into my kits only those well grown, 

 as shown by the length of the wing-cases, which should reach the middle 

 of the abdomen. But if, when a species is becoming common, one will 

 go to the edge of the water it frequents, at the time of its emergence, one 

 may find nymphs crawling from the water, others transforming, imagoes 

 drying their wings, and others ready to fly, and may thus obtain in a few 

 minutes the material necessary for determining nymph and imago. The 

 time of emergence may be determined by noticing at what time pale 

 young imagoes are seen taking their first flight, and then going out a little 

 earlier. The unfortunate thing about it is that many of the larger species 

 transform very early in the morning, and to take such advantage of them 

 one must be on the ground between daybreak and sunrise. 



Several imagoes should be kept alive until they have assumed their 

 mature colours. It is most important that each imago and its cast skin 

 should be kept together. 



Eggs, also, are easily obtained. Every collector has seen the female 

 of the species figured on the front of this magazine, or of related species, 

 dipping the tip of her abdomen into the surface of the water, depositing 

 eggs. If the ovipositing female be captured, held by the fore wings, 

 leaving the hind wings free, and " dipped " by hand to the surface of 

 clean water in a vial or a tumbler, an abundance of eggs will usually be 

 liberated. Eggs of those species which possess an ovipositor and which 

 place them within the tissues of plants may be obtained by collecting 

 the stems in which they have been inserted. 



Eggs and nymphs should be dropped in boiling water for a minute 

 and then preserved in alcohol. Imagoes, if mounted, should have a 

 wire or bristle inserted into the body its entire length to prevent otherwise 



