, GEORGIAN BAY EPHEMERIDJE 127 



SESSIONAL PAPER No. 39b 



with irregular light areas. Dorsum of abdomen brown except lateral margins 

 which are colourless; on each segment there are 2 small oblique pale streaks and 

 2 round dots posterior to the streaks. Setse pale with brown band toward distal 

 end; lateral setse fringed on inner sides only. Gills double, apparently on seg- 

 ments 1 and 2 only; broader than gills of Bcetis; a main trachea in each, slightly 

 to outer side and branchlets on inner side only. Legs pale; femora banded with 

 brown in distal half; tibiae and tarsi brown toward proximal ends; claws com- 

 paratively long, sharp-pointed, and not pectinated. 



The nj^mphs were not very abundant; my collections date from July 30 to 

 Aug. 12. . 



Imagos were reared July 30 and August 2. Adults were quite numerous 

 at Station Island about July 10, flying in small swarms along the shore, at a height 

 of from 10 to 15 feet. They appeared about 7 -45 in the evening. 



This paper and the following one on the genus Heptagenia contain the results 

 of but a few months collecting and rearing. The complete life histories of 9 new 

 species were secured and the hitherto unknown nymphal stages of 9 other species 

 determined by rearing. Besides a few observations on the habits of several species 

 have been recorded. The results may be taken as an indication of the richness 

 of our inland waters in aquatic insect life. 



I am adding a diagram showing the length of time imagos of these species 

 were seen, captured or bred. I find in a number of instances that the dates are 

 somewhat later than those given for the same species at Fall Creek, Ithaca, New 

 York. 



REFERENCES. 



1877. L'ABBfi L' Provancher. — Faune Entomologique du Canada, et ParticuliSrement de la 

 Province de Quebec. Vol. II. 



1888. Eaton, Rev. A. E. — A Revisional Monograph of Recent Ephemeridse or Mayflies. Trans, 

 of the Linnoein Soc, Second Series, Vol. Ill, Zoology, London, 1883. 



1901. Needham, J. G. — Aquatic Insects in the Adirondacks. New York State Museum, Bulletin 

 47, 1901. 



1904. Needham, J. G. — Mayflies and Midges of New York. New York State Museum, Bulletin 

 86, 1904. 



1911. MoBQAN, Anna H. — Mayflies of Fall Creek. Annals of the Entomological Society of America, 

 Vol. IV, No. 2, 1911. 



1913. Clemens, W. A. — New Species and New Life Histories of Ephemeridae or Mayflies. 

 Can. Entomologist, Vol. XLV, Nos. 8 and 10. 



