10 INSECUTOR INSCITI^ MENSTRUUS 



The coloration in the Yukon takes on a generally different 

 character. Instead of dull stone gray, mixed with black and 

 with dark brown shades and diffused lines, the mesonotum 

 becomes bright clear gray with a little brown suffusion cen- 

 trally. The brown may be absent, or overspread the whole 

 mesonotum, sometimes with the addition of a pair of star-like 

 whitish spots, but without blackish lines. 



The larvae occur mixed with those of decticus. I have speci- 

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

 British Columbia. 



Larva. Head-hairs both single, long, the ante-antennal tuft 

 in four. Lateral comb of the eighth segment of 12 large scales, 

 each with a very long central thorn and small lateral spinules. 

 Air tube about two-and-a-half times as long as wide, the 

 pecten evenly spaced, followed by a two-haired tuft, after 

 which are three widely detached teeth, the third toward the 

 apex of the tube. Anal segment with a large plate, quadrately 

 emarginate on the side posteriorly, the anterior part approach- 

 ing the ventral line and irregularly edged. 



Eggs of prodotes were obtained from captured females at 

 White Horse. They are thickly fusiform, rounded, one side 

 flattened, the ante-micropylar end more pointed than the other, 

 shining black. They were deposited on the bottom of the glass 

 jar, under moss, in little groups of half a dozen. 



The adults prefer open or semi-open country. The males 

 swarm, not over projecting objects, but over the spaces be- 

 tween. At White Horse and Atlin, the males were frequently 

 seen just after sunset swarming singly or in small groups over 

 bare ground between willows or small pines, some ten feet in 

 the air. Under tall pines or in spruce forest they were never 

 met with. The swarming habits as given by me (Ins. Ins. 

 Mens., vii, 22, 1919) really belong to decticus. 



Total, 1,973 specimens: (Yukon region) Skagway, Alaska, 

 July 28, 1919; Inspiration Point, Alaska, July 28, 1919; White 

 Pass, British Columbia, July 28, 1919; Atlin, British Columbia, 

 July 22-25, 1919 ; Carcross, Yukon Territory, June 26, July 21, 

 27, 1919; White Horse, Yukon Territory, June 26-30, July 



