J HE CANADIAN ENTOMOLOGIST 193 



males of the American form from those of the European form 

 by the shape cf the abdominal appendages. The difference is 

 slight, but constant in the material I have examined. 



In the second place, ha\ing recently reared cyathigerum at 

 Toronto, I find that the n\-mph decs not wholly agree with Ris' 

 description and figure (I have not had access to Lucas' description), 

 but that, on the other hand, it is so extremely like that of calverti 

 that a comparative study of these forms is necessary in order to 

 make their separation possible. 



Early in June, 1914, I found E. cyathigerum in considerable 

 numbers at "Fisherman's Island," a long narrow sand bar, south 

 of the city, which separates Ashbridge's Bay from the open lake, 

 and, until recent filling-in operations commenced, was margined 

 on the inner side by a wide extent of marsh. If proved too late to 

 obtain the nymphs that season, but on May 24 of the following 

 year a visit was made to the same spot and about twenty mature 

 nymphs were secured. They were accompanied by large numbers 

 of E. hageni. On May 26 a male cyathigerum emerged, and as the 

 identity of the nymphs was now assured, the remainder was 

 preserved for study. Images had already become quite numerous 

 on the island, and soon became abundant. A large number were 

 examined, but all were alike; no specimens of calverti were found 

 among them. Shortly afterwards they disappeared and were 

 followed, as in the previous year, by swarms of E. hageni. 



During the season of flight of cyathigerum, E. calverti was 

 common about a pond in the vicinity of my house in Wychwood 

 Park, Toronto, and I reared this species again here, as I had 

 previously done at Lake Simcoe and Go-Home Bay, Ont. I was 

 thus able to obtain sufficient material for a comparison of the 

 nymphs of the two species. 



The Nymph of Enallagma cyathigerum. (PI. IX). 



Very similar to E. calverti Morse in size, form and coloration 

 {v. Can. Ent.. XLV, 1913, p. 1B2, pi. 1, figs. 4, 5). Head as in 



1. British Dragonflies, pp. 297-307. 



2. Die Siisswasserfauna Deutschlands. Heft 9, Odonata, pp. 50, 54. 



3. Can. Ent.. XLV, No. 6, p. 162. 



4. Proc. .A.cad. Ind., p. 121. 



