82 Transactions of the Royal Canadian Institute 



Abdomen black, with basal segmfental white bands; venter mostly 

 whitish. Legs black, the femora white beneath; knjse-spots pale. Wdngs 

 broad, the cross-veins nearly in line, the scales all blackish, coarsely 

 linear; a small tuft at base of third vein, but no scales on the cross-veins. 



The male genitalia have the unci simple; a long row of spines on the 

 penultimate segment. 



The larvae live in dark perman,ent pools in the forest, where they are 

 frequently much preyed upon by Eucorethra underwoodi larvae. The 

 adults hibernate; the eggs aire deposited in broad roundedly triangular 

 rafts on the surface of the water. 



Distribution : Northern forests from the Atlantic to Pacific, moun- 

 tains of California to Alaska. 



Canadian Records. 



Martin's Fall, Ontario (Walker). 

 White River, Ontario, June, 1918 (H. G. Dyar). 

 Red Deer, Alberta, August i, 1918 (H. G. Dyar). 

 Sm^ith Landing, Alberta, May 30, 1911 (H. V. Radford). 

 Fort Simpson, Mackenzie, April 21, 19 14 (E. A. Preble). 

 Kalso, British Columbia, July 19, 1903 (H. G. Dyar). 

 Terrace, British Columbia, August 14, 1919 (H. G. Dyar). 

 Caulfields, British Columbia, May 3, 1919 (E. Hearle). 

 Agassiz, British Columbia, June i, 19 17 (A. E. Cameron). 

 Prince Rupert, British Columbia, May 14, 19 19 (H. G. Dyar). 

 Clayburn, British Columbia, March 25, 1919 (E. Hearle). 

 Hatzie, British Columbia, April 14, 19 19 (E. Hearle). 

 Hope, British Columbia, May 20, 19 19 (E. Hearle). 

 Whitehorse, Yukon Territory, July 3, 19 19 (H, G. Dyar). 

 Dawson, Yukon Territory, July 15, 19 19 (H. G. Dyar). 



Genus Mansonia Blanchard. 



A small genus of general distribution, the species more numerous in 

 the tropics. The larvae are peculiar in having che air- tube adapted lor 

 piercing the vascular roots of certain aquatic plants, from which they 

 get their supply of air. The eggs are deposited in rafts in swamps where 

 suitable plants grow, and the young larvae descend to the roots, never 

 coming to the surface again. 



The genus has been divided into subgenera on genitalic characters 

 (Dyar, Ins. Ins. Mens., vi, 112, 1918). The single Canadian species 

 belongs to the subgenus Coquillettidia Dyar. 



