142 MARINE AND FISHERIES 



5 GEORGE v., A. 1915 



of head. A black dot below each antenna, in front of each eye and near inner margin 

 of each eye. 



Thorax lighter in colour than head; on each side of pronotum, near median 

 line is a small light spot; just lateral to this is a triangular dark spot and lateral 

 to this again is another light area. In anterior angle of pronotun is an oval light 

 spot. Along posterior margin extending some distance on either side of median 

 line is a broad light band, which is connected by a light longitudinal stripe along 

 median line of mesonotum, to a large irregular light area on the mesonotum. 



Abdomen usually light yellowish brown; the colour pattern, roughly, has the 

 appearance of a broad light band along median line in which, on segments, 5, 6, 

 and 7 are oval dark areas, in 8 a narrow stripe and in 9 a round dark area in each 

 segment, on either side of this broad light band is a short light stripe; ventral 

 surface almost white with 2 lateral light brown longitudinal stripes on segments 

 1-9; a broad band across 9th along posterior margin, joining the 2 lateral stripes. 

 Segments of setae alternately light and brown. Legs pale, colour pattern similar 

 to H. canadensis. 



This species was not nearly so abundant or wide-spread as H. canadensis. 

 Nymphs were taken in quite similar localities and at about the same time. They 

 were taken from June 15 to July 2, and imagos reared from June 26 to July 4. 



Heptagenia sp. indet. 

 Nyn^vh: (PI. XVI, Fig. 5). 



Measurements: Body 10-11 mm.; setae 12-13 mm. 



Head light brown; sometimes 3 light areas along entire margin but frequently 

 middle one is lacking and the 2 lateral ones are connected with the light margins 

 lateral to eyes. An almost black spot in centre of each half of pronotum; around 

 this is an irregular light area, exterior to which is a brown area. Abdomen whitish 

 yellow with 5 longitudinal yellowish brown stripes in each segment 1-8. Setae 

 light greenish yellow; joints abundantly fringed with hairs. Legs yellowish brown 

 in colour; pattern similar to the 2 preceding species. 



Mr. R. P. Wodehouse kindly gave me these nymphs which he collected along 

 the east shore of Manitoulin Island on June 26th, 1912. As they were not reared 

 the species cannot be ascertained at present. 



REFERENCES. 



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

 of the LinncBan Society: Second Series, vol. Ill, Zoology; London, 1888. 



1901. Needham, J. G. — Aquatic Ingects 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. 



1910. Banks, Nathan. — Ephemeridae of the Genus Heptagenia. Can. Entomologist, vol. XLII. 

 No. 6, 1910. 



