INSECUTOR INSCITI^ MENSTRUUS 9 



17, 1919). The larvae are quite distinct. I have larvae of 

 decticus from Banff, Alberta (Dr. C. G. Hewitt), and from 

 Dawson, Yukon Territory, agreeing essentially with lazarensis. 

 In these larvae the anal plate is more sharply marked than in 

 the specimens I described from Plattsburgh, New York (Ins. 

 Ins. Mens., vii, 21, 1919), ending sharply, but irregularly at 

 some distance from the ventral line. 



This species prefers densely forested country. The males 

 swarm low near the ground, under trees, as described by me in 

 error for prodotes (Ins. Ins. Mens., vii, 22, 1919). The 

 swarming habits of prodotes are really quite different. 



Total, 433 specimens : Edmonton, Alberta, May 1-5, 1919 ; 

 Prince George, British Columbia, May 11-17, 19-22, 1919; 

 Skagway, Alaska, June 24, 25, 1919 ; Atlin, British Columbia, 

 July 22-25, 1919 ; White Horse, Yukon Territory, June 26-30, 

 July 1-8, 16, 1919 ; Tahkeena River, Yukon Territory, July 19, 

 1919; Hootalinqua, Yukon Territory, July 6, 1919; Horse 

 Falls, Yukon Territory, July 13, 1919 ; Dawson, Yukon Terri- 

 tory, July 7-11, 13, 14, 1919. 



Aedes prodotes Dyar. 



A'edes prodotes Dyar, Ins. Ins. Mens., v, 118, 1917. 

 I referred to this as the "Rocky Mountain form of decticus" 

 (Ins. Ins. Mens., vii, 22, 1919), but the appellation is incorrect, 

 for while prodotes is not certainly known east of the Rockies, 

 decticus crosses the range and inhabits the Yukon Valley, the 

 two species occurring together. I previously called all speci- 

 mens from the Rockies and westward prodotes, but now find 

 that both occur at Banff. Thus prodotes is more of a high- 

 altitude species, the records in the west cited by me, Field and 

 Mt. Cheam, B. C, being correct. On the other hand, the 

 troublesome female from White River, Ontario, June 25, 1907 

 (F. Knab), which was placed under trichurus in the mono- 

 graph, and under decticus by me, appears in the light of latest 

 information to be prodotes. If so, this is the easternmost 

 record. The range of prodotes is to the north along the higher 

 mountains of the Rockies into the Yukon Valley where it is 

 the second species in abundance. 



