98 BUTTERFLY SOUNDS 



which it seems to me signalizes their use, in that 

 in the midst of scales more lightly attached and 

 easily removed than are those of any other bnt- 

 terflies, it is impossible to remove one of these 

 without breaking the wing ; they are firmly set 

 bristle-scales, and on the opposing part of the hind 

 wings, in the marginal interspace, is a similar 

 patch, not so characteristic, of rounded pavement- 

 like scales. If any noise is produced by the move- 

 ment of the wings, it must be by the agency of 

 these two opposing fields. 



Special movements of some sort are made by a 

 majority of butterflies; as for instance in most of 

 our Argynnini and other Nymphalinae, which gen- 

 tly wave their wings upward and downward upon 

 alighting, as if panting from their exertions. A 

 marked instance of this is seen in the Red Admiral 

 (Vanessa atalanta). Still more striking instances 

 are the quivering movements of the male settled 

 beside the female ; or of a butterfly eagerly suck- 

 ing a flower when another alights beside it, and is 

 thus^warned to " keep its distance." These mo- 

 tions I am inclined to regard as movements for the 

 sake of producing sound, though the sounds are 

 inaudible to our ears. It is probable that this is 

 on account of their faintness. There is a limit to 



