328 Mr. G. T. Bethune-Baker's Notes on the 



sections vertically, which are not separated from each 

 other but are attached, the hind section to the short girdle 

 and the fore section to the upper part of the clasps, and to 

 hind section by very similar chitinous arms that hang down 

 almost vertically, through which the anal orifice passes 

 high up just below the dorsal plate. The sternite portions 

 diSer, however, in some important characters. The clasps 

 in each genus are curtained over on the fore part of the 

 upper margin. In Cossus cossus the fulcrum is replaced 

 by a large organ attached to the base of the clasp and to 

 the juncture of the girdle and tegumen, consisting of two 

 erect broad rounded and shagreened chitinous plates, the 

 lower part of which is produced forwards into two long 

 strong horns, whilst the upper part extends in a sort of 

 chitinous muscular extension and gradually fuses with the 

 clasp, forming a hollow resting-place for the aedoeagus, 

 which is a moderately broad somewhat curved tube of 

 fairly even width expanding slightly towards the orifice. 



In Duomifus leuconota the curtain of the clasps is in the 

 rear of the upper margin, not in the forepart as in Cossus, 

 and it is a fine membranous curtain, not a strongish bridge 

 as in that genus. The organ replacing the fulcrum is a 

 very large recurved outer tube extending well to the rear 

 of the girdle and terminating about a third from the apex 

 of the clasp, the front aperture being the full width of the 

 tube ; in this lies the aedoeagus, which is by no means large 

 for the size of the insect ; it is ribbed for most of its length, 

 and has a long tapered extremity. From the armature 

 one would surmise that in both these genera we have the 

 persistence of a primitive type of genitalia. 



Turning now to the Psychidae, inasmuch as the females 

 are apterous to all intents and purposes, we should expect 

 to find that the male armature is modified, and so it is to 

 some extent, but we find nevertheless quite decided differ- 

 ences between the genera. The marked character of the 

 group is the very simple large tegumen forming a simple 

 covering or hood over the greater part of the organs. 



In Psyche viciella, SchifE., the hood is very large, covering 

 about two-thirds of the segment (this does not come ouc 

 adequately in the figure), the hind part of the tegumen 

 extending on to the ventral surface ; below this is a small 

 ventral plate to which the clasps are attached; these are 

 quite small and primitive, almost finger-shaped, but rather 

 wider at the rear. The aedoeagus is long and curved, with 



