92 John Henry Comstock 



in all) more than 94 per cent, were males. It is not at all 

 likely that this represents the difference in the numbers of in- 

 dividuals of the two sexes ; it is much more probable that the 

 difference is due to a greater activity on the part of the males. 



While I believe that the greater specialization of the wings 

 of the male is due to the greater activity of that sex, I confess 

 that I am greatly puzzled by the fact that in no female of the 

 Macrofrenat^ has a consolidated frenulum and a frenulum 

 hook been developed.* In other respects the females, as a 

 rule, lag behind the males in their specialization only a short 

 distance. But while the possession of a consolidated frenulum 

 and a frenulum hook is attained by the males in the most gen- 

 eralized of living frenate moths, that stage is not reached by 

 the females of the most specialized genera. Obviously there 

 is a factor here that I have not discovered. 



A similar lagging behind of the females is shown in a 

 marked way in the specialization of the antennse in the Satur- 

 niidse. Here in the more generalized genera (Coloradia and 

 Hyperchirid) the antennse of the male alone are pectinate. 

 In Colosaturnia the female has attained pectinate antennse 

 but unlike those of the male each segment bears only a single 

 pair of pectinations. In the remaining genera of our fauna 

 both sexes have pectinate antennse and in each case each seg- 

 ment of the antennse bears two pairs of pectinations ; but the 

 antennse of the male are much more highly developed than are 

 those of the female. If, as seems probable, the antennse are 

 organs of smell, and if, which also seems probable from cer- 

 tain well known experiments, the males in this family arfe 

 guided to the females by the sense of smell, it is easy to under- 

 stand the higher specialization of the antennae of the males in 

 this family. 



In this discussion of the taxonomic value of the wings, I 

 have confined myself chiefly to a study of the form of the 

 wings, their venation, and the relation of the two pairs to 

 each other. But I believe that even the clothing of the wings 

 is of great taxonomic value. 



* I have not studied the MicrofrenatiE enough to be in a position to 

 make generalizations regarding them. 



