THE CANADIAN ENTOMOLOGIST 59 



are exactly as in postera and asteroides. A dark brown streak 

 bordering the full length of the inner margin exists in all omissa 

 under examination, and is usually more obvious than in asteroides, 

 much more so than in postera, from which it is often altogether 

 absent. Size of asteroides. 



Described from IS d" & and 8 9 9. Localities: 5 d" cf , 2 9 9 , 

 Head of Pine Creek, near Calgary; May 18th (one), June 25th to 

 August 13th, collected by the author; one pair, Windermere, B. C, 

 July 12th, 1907 (the author); 1 9 , Nelson, B. C. (H. Cane); 1 d^, 

 3 9 9, Aweme, Man., June 6-14, 1910 (Criddle) ; Q dd, Cart- 

 wright, Man. (Heath collection); 1 9, Hymers, Ont., July 11th, 

 1912 (H. Dawson); and 1 9, Breezy Point, N.H., July 2-9, 1912 

 (L. W. Swett). 



Types — cf in the author's collection, 9 in that 

 of Dr Wm. Barnes. Both Calgary specimens. My notes tell me 

 that there is a specimen of this species in the British Museum from 

 Denver, Colo., as well as typical asteroides from the same locality. 

 I also have a Denver asteroides in my own collection. 



Omissa is the No. 359 of my Alberta list, originally entered 

 as postera on Smith's authority, and is the postera of the Kootenai 

 and B. C. lists (Can. Ent., XXXVH, 227, June, 1905, and XLV, 

 94, April, 1913). The Manitoba specimens, some of which I am 

 making co-types, are the darkest of the lot both in primaries and 

 secondaries, and compared with Calgary, B C, and Ontario speci- 

 mens, have less of the rusty red through and beyond the cell, 

 and contrast more strongly with asteroides. In fact, though I 

 choose the actual types from Calgary, it was a study of Manitoba 

 material which finally decided me that the form was distinct. I 

 found a short series of both omissa and asteroides in the Heath 

 collection, and Mr. Wallis kindly loaned them to me for study. 

 They were all on short pins, and it is reasonable to suppose. that 

 they were collected at Cartwright, especially as both have been 

 taken at Treesbank, about fifty miles distant. 



Mr. Tams has prepared two mounts of male genitalia of 

 omissa, from Calgary and Aweme, and we have compared them 

 with two of asteroides from Chicago and Cartwright, and one of 

 British asteris, which agrees closely with Pierce's figure and de- 

 scription. The two omissa diff'er from the two asteroides in one 



