256 THE CANADIAN ENTOMOLOGIST. 



Heptagenia nibromaculata, sp. no v. 



Male imago. 



Measurements: Body 8 mm.; wing 8; setae 17; fore leg 7. No 

 markings on face; darker spot at posterior margin of head between 

 eyes. Thorax dark; median longitudinal dark stripe on pronotum; 

 dark brown stripe on coxa of fore leg and extending up the side of 

 prothorax. Abdominal segments 1-7 light; 8-10 dark, similar to 

 thorax; each segment banded at posterior margin; stigm.al dots 

 distinct; wing has a reddish area in pterostigmatic space. 



Female imago. 



Measurem.ents: Body 9-9.5 mm.; wing 13-14; setae 15-22; 

 often slightly reddish on face beneath antennae. Dark brown on 

 dorsal surface of head behind ocelli. Abdomen varies from reddish 

 to a 5'el!owish colour in dried specimens. 



Nymph. 



Measurements: Body 9-10 mm.; setae 10. Head dark brown, 

 dotted with minute light spots. Pronotum" similar in colour to 

 head; two light areas on each side, the outer one sometimes joined 

 to the light margin. Abdomen dark brown, with a granular ap- 

 pearance; sometimes a faint, broad, dark, longitudinal streak can 

 be made out with two dots on each side of it on each segment ex- 

 cepting 9 and 10; ventral surface lighter, with a median row of ir- 

 regular dark spots and lateral rows of small dots or lines; the 

 median dots are sometimes broken up so that only four or fl^'e 

 small dots remain in its place; on segment 9 the markings are usu- 

 ally joined, forming roughly three sides of a square. Femur with 

 four irregular dark bands ; both posterior and anterior margins very 

 hairy; claws pectinated. A very hairy species, having anterior 

 margin of head, sides of thorax and abdomen very hairy. 



This nymph was first taken on June 15 in w^hat is commonly 

 called the Narrows, near the mouth of the Go-Hom.e River. The 

 water here had a well-marked current, but not swift. On June 30 

 I found them very numerous in the very swift water of a rapids 

 near the mouth of the Muskosh River. Nearly a month after this, 

 on July 20th and 22nd, I discovered mature nymphs at an old lum- 

 ber chute on the Go-Home River in fairly swift water. Imagos 

 were bred from the nymphs taken at the Narrows on June 22nd and 



