340 THE CANADIAN ENTOMOLOGIST. 



distinct on segments 9 and 10 only; 9th pale with a short median 

 longitudinal brown stripe commencing at anterior margin ; on each 

 side of this is a short stripe of about same length, but placed more 

 posteriorly; lateral to this, again, is a large brown area, roughly 

 triangular, apex at posterior margin, base at anterior; at lateral 

 margin, slightly below middle line, is a small brown spot; on the 

 10th segment is a median brown longitudinal stripe, with two dots 

 on each side of it. Ventral surface of abdomen white, with three 

 longitudinal brown stripes, one median and two lateral. Gills on 

 segments 1-7, double on 1, 2 and 3. Three setae of equal length; 

 lateral ones fringed with hairs on inner margins only, except tips; 

 all banded toward distal end with brown. Legs pale; femur with 

 proximal end brown and a brown band beyond middle; tibia with 

 a brown band about the middle; tarsus with brown band toward 

 proximal end ; fore tarsus much longer than fore tibia; hind tarsi only 

 slightly longer than hind tibia?; fore claw rather short, broad and 

 bifid at tip; hind claws about twicelengthoff3re, and very pointed. 



Baelis prGpinqmis Walsh. 



The imago is described in Eaton's Monograph, but my speci- 

 mens do not show the subopaque area between the two nervures of 

 the hind wing. Nymphs were taken at Go-Home Bay from June 

 14th to July 22nd; on August 19th large numbers of them were 

 discovered in a little bay of a small, bare island about three miles 

 out in the open. This rock was the home of numerous gulls, and 

 hence is commonly called "Rookery" Island. The nymphs were 

 mature, and images emerged on August 21st and 22nd. 



Nymph: (PI. VI, fig. 6.) 



Measurement — Body 6 mm.; seta? 2 mm. Face vertical, 

 mostly brown in colour; on dorsal surface of head on each side of 

 median line is a row of irregularly-shaped light spots. Notum brown 

 with various light areas. Dorsum of abdomen for the most part 

 brown; segments 2-4 brown, with a light area in each half of each 

 segment, and margins colourless; on segment 4 there is also a light 

 area in median line; segment 5 quite light in colour; segment 6 

 brown, with a light area along anterior margin and two faint ones 

 posterior to it; segments 7 and 8 each with two rather large pale 

 areas in posterior half; segment 9 almost entirely pale; segment 10 



