INSECUTOR INSCITI^ MENSTRUUS 107 



determinable by the adults alone. I would have expected 

 mimesis, which occurs at Kaslo, British Columbia, to the north- 

 ward of this region, and the character of the breeding ground 

 — marshes — indicates this species rather than the river-pool 

 sansoni; but the wing scales are as in sansoni. 



Aedes pullatus Coquillett. Two females. A large species 

 of the black-legged group, the mesonotum clothed with dark 

 brown scales without dark bands, the wing-scales black. This 

 does not agree well with pullatus, but in the absence of full 

 data I do not venture to separate it. 



Aedes aestivalis Dyar. Two females. A smaller species 

 of the black-legged group with gray lateral vestiture on the 

 mesonotum. Both specimens are worn and in too poor shape 

 for exact determination ; but as aestivalis abounds at Sand- 

 point, Idaho, in a not wholly dissimilar region, the determina- 

 tion is made tentatively. 



(2) Missoula, 3,223 feet. Situated in the broad prairie 

 flood -plain of the Hell Gate River at the junction of two 

 forks. The plain is surrounded by high hills, mostly bare of 

 trees on their aspect toward the town, but wooded on the 

 northern slopes toward the river canyon. 



Aedes idahoensis Theobald. Eighty-seven males and fifty- 

 three females. Of the latter 20 are atypical, having the black 

 and white scales on the wings not contrasting, though some 

 are at least pale, and so transitional toward aldrichi Dyar & 

 Knab. 



Aedes vexans Meigen (syhestris Theobald). Eight males 

 and fifty-seven females. 



Aedes sansoni Dyar & Knab. Twenty- four males and forty- 

 seven females. 



Aedes cinereus Meigen {fuscus Osten Sacken). Five 

 females. 



Aedes triseriatus Say. One female. 



Aedes sp. One female with black legs and black wing- 

 scales, possibly a specimen of pullatus strayed from the for- 

 ested hills above. The specimen is badly rubbed. It was 

 taken in Reno Park in the well-forested river bottom. 



