342 THE CANADIAN ENTOMOLOGIST. 



corrugations of the last two segments are faint and irregular. The 

 spiracles are distinct at the sides of all the abdominal segments excepting 

 the first. 



The abdominal segments from the third to the seventh bear each two 

 parallel and toothed carinie across the dorsum. The anterior of these is 

 situated at a short distance from the anterior margin of the segment, and 

 begins (see 7th) on each side immediately cephalad and slightly ventrad 

 of the spiracle. The posterior carina is parallel with the first, on the 

 fourth, fifth and sixth segments, and extends in an irregular line across the 

 venter. It is bent strongly caudad and considerably raised on the mid- 

 ventral line. On the third and seventh segments the posterior carina is 

 indistinct. The anterior carina of the seventh segment is continued across 

 the venter, bent strongly caudad and strongly raised. The last segment is 

 hemispherical, marked by several more or less distinct, concentric carinae, 

 scattered tubercles, and a slit-like protuberance at the tip. The armature 

 just described is undoubtedly of great assistance to the remarkably active 

 pupa in working its way from the burrow or from the cocoon previous to 

 transformation. The pupal skins are usually found projecting amongst 

 leaves and rubbish on the surface of the ground near the mouth of the 

 burrow, which is usually at or slightly below the surface. Sometimes, 

 however, the pupal skins are found within the mouth of the tunnel. 



During transformation the cuticle splits along the Y-shaped sulci on 

 the dorsal surface of the head and along the line mentioned before as 

 extending across the head and thorax. The split ends at the first ab- 

 dominal segment. On the venter the cuticle usually splits on the middle 

 line as far as the middle of the fourth abdominal segment. The somewhat 

 triangular portion of the cuticle covering the antennae, eyes and bases of 

 the palpi is invariably broken off. 



The length of the pupal period is at least twelve days. A pupa, 

 apparently recently pupated, was obtained June 28th, 1909. The adult 

 emerged twelve days later at 5 p.m. 



We frequently collect the adults in the early evening (6 to 8 p.m.) by 

 picking them from the bases of the willow stems, where they rest, head 

 upwards, about six inches from the ground. Very often a number of wings, 

 usually perfect, will be found at the base of the clump of willows, with the 

 body completely vanished. The pupal skin is usually nearby. The 

 robbers were not discovered, but doubtless mice are responsible. 



