418 



THE CANADIAN ENTOMOLOGIST 



to sixth from the outside longest; lateral setae 11, sometimes 10. 

 Abdomen somewhat elongate ovate, broadest at seg. 6, or at apical 

 margin of seg. 5, tapering almost equally proximad and distad, its 

 lateral margins forming an almost regular arc, fringed with spinules 

 distally, especially on segments 8 and 9. Dorsal hooks wholly 



l^'ig. 20. — Leucorrhtnia horealis. Hag., nymph. 



absent. Lateral spines of seg. 8 about one-seventh to one-fourth 

 as long as the lateral margins of the same segment (not including the 

 spine) their inner margins nearly parallel ; those of seg. 9 about 

 two-fifths the length of the lateral margin of the segment, not reach- 

 ing apices of lateral appendages, their inner margins slightly con- 

 vergent. Superior appendage triangular, keeled and somewhat 



