THE CANADIAN ENTOMOLOGIST. 



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Explanation of Plates. 

 Plate V. 



Photographs of Mayfly Nymphs. 



Heptagenia tripunctata Banks. 

 Heptagenia lutea sp. no v. 

 Heptagefiia canadensis Walker. 

 Heptagenia sp ? 

 Heptagefiia frontalis Banks. 

 Heptagenia rubromaculata sp. nov. 

 Heptagenia ftcsca- sp. nov. 

 Heptagenia flavescens Walsh. 

 Heptagenia flavescens (ventral view). 

 Ecdyuriis pulliis sp. nov. 

 Ephemerella lineata sp. nov. 



Plate VI. * 



Nymph Hexagenia bilineata Say. 



Nymph Heptagenia luridipennis Burm. 



Nymph Ephemerella bicolor sp. nov. 



Ecdyurus maculipennis Walsh. 



Nymph Ecdyurus lucidipennis , sp. nov. 



Nymph Bcetis propinguus Walsh. 



Nymph Cloeon duhium Walsh. 



Venation of wing pad of nymph of Siphlurus flexus 



Fore claw of nymph of S. flexus sp. nov. 

 Fore claws of imago of S. flexus sp. nov. 

 Wings of Siphlurus flexus sp. nov. 



Plate VII. 

 Mouth parts, gills and genitalia of Heptagenia canadensis and 

 H. tripunctata. 



Labium and 2nd maxilla, H. canadensis. 

 First maxilla, //. canadensis. 

 Mandible, H. canadensis. 

 Labrum, H. canadensis. 

 Hypopharynx, //. canadensis. 

 Genitalia, H. canadensis. 



