39 



ber of free segments, and in the fact that all the appendages are 

 firmly soldered to each other and to the body. The antennae, how- 

 ever, are of a different type, being pectinate in the Cossoidea. The 

 metathorax varies considerably from the generalized type, being very 

 much shorter, so that the mesothorax is about four times its length, 

 measured on the median line. Many of the species in this superfamily 

 have larvae which are borers, and many of the pupae are fitted to work 

 their way to the surface of a burrow. However, the ventral plate of 

 the seventh abdominal segment, which is so distinct in the Hepialoi- 

 dea, is not present. All of the pupae have some of the body segments 

 armed with spines and strongly toothed chitinized ridges, and a 

 strong ridge or projection is generally present on the head. The 

 families may be separated as follows : 



a. Abdominal segments 2-6 movable in the female and 2-7 in the male ; 

 dorsum of abdominal segments armed with a row of sharp spines 

 on the cephalic margin, and a row of setae, which are directed 

 cephalad, on the transverse conjunctiva at the caudal margin; 

 females without Avings and antennae and larva-like in appearance. 



Psychidae. 



aa. Abdominal segments 3-6 movable in the female and 3-7 in the male ; 

 dorsum of abdominal segments armed with a toothed ridge along 

 each margin ; sexes similar Cossidae. 



Family Psychidae 



In this family there are no sutures apparent on the head except 

 between the clypeus and labrum and the mandibles. The antennae 

 are short and pectinate. The prothorax is longer and the meta- 

 thorax much shorter than in the Hepialoidea, to which, however, 

 these pupae show many resemblances. The dorsum of the abdomen 

 has toothed chitinized ridges along the cephalic margin of some of 

 the segments and rows of setae along the caudal margin on the trans- 

 verse conjunctiva. The caudal end of the body bears two large, 

 strong hooks directed ventrad. This description applies mostly to 

 the males (Figs. 11-13), as the females are quite different as seen in 

 Figure 14. 



The females never leave the cocoon during their entire life and 

 have no provision for locomotion, even in the adult. It is an aston- 

 ishing fact that no pupal wings are developed, because in all other 

 families where the adult females are apterous the pupal wings are 

 always developed, sometimes as much as in the males. Neither are 

 there any pupal antennae present, no eye-pieces, nor traces of maxillae. 

 The labrum and mandibles show very distinctly, both being consid- 



