38 



Sthcnopis tlutle were obtained through the courtesy of Mr. J. M. 

 Swaine, of the Canadian Department of Agriculture, who obtained 

 them from the stems of willow at MacDoiiald College, Quebec. 



Family Hepialidae 



The pupae of this family are very generalized as to the number of 

 sutures present in the head, the number and arrangement of append- 

 ages, the comparative length of the mesothorax and metathorax, and 

 the nearly equal length of the first seven abdominal segments. These 

 characters are easily seen in Figures 8-10 and need no further de- 

 scription. The pupae are, however, exceedingly specialized as to the 

 chitinization of the body, the spines, toothed ridges and cutting plates 

 on the abdominal segments, and, more than all, in the soldering down 

 of all the appendages to each other and to the body, exactly as in the 

 most specialized of pupae. The head, thoracic segments, and the first 

 two abdominal segments are firmly soldered together, but abdominal 

 segments 2-7 are free in the male and 2-6 in the female. 



The only consolidation of the head parts is that of the clypeus 

 and labrum, between which the suture has been lost. The antennae, 

 as well as all the other appendages, are very short in comparison with 

 the length of the body. These pupae are of considerable size, that 

 of Sthcnopis tlutle being about 30 mm. in length. The larvae as far 

 as known are borers, and their pupae have special adaptations for cut- 

 ting their way to the surface. The most peculiar of these adaptations 

 is the ventral plate on the seventh abdominal segment (best seen in 

 Figure 9), which has not been found in any other pupae examined. 

 The sharp ventral projections on the front also serve as cutting sur- 

 faces, but similar projections are found in many pupae, particularly 

 among other species whose larvae are borers and in very many of the 

 leaf-mining species. The opening of the mesothoracic spiracle has 

 reached the normal position for most lepidopterous pupae, being be- 

 tween the prothorax and the mesothorax at each caudo-lateral angle 

 of the former. The genital opening is found in the male on the meson 

 of the ninth segment between two slightly elevated tubercles. In the 

 female there is a single opening apparently on the eighth segment. 



The following species was examined : 

 Sthcnopis thulc Strecker. 



Superfamily COSSOIDEA 



The pupae of this superfamily are less generalized as to head 

 parts than the Hepialoidea, but nevertheless resemble them very 

 closely in size, shape and arrangement of the appendages, in the num- 



