308 



The v. antiopa is only a migrant to this country and seldoin seen, 

 but it breeds in Europe and northern Asia, commonly along willow- 

 bordered streams. I have a few specimens from the banks of the Po, 

 and from one of these I have detached the fore wing. (See Fig. 71 .) 



Pig. 71. — Diagram of fore wing of Vanessa antiopa (original). 



Along the hinder edge of this I notice a smooth projecting vein, &, to 

 run, which looked at in the direction, a, is seen with a strong magnifier 

 to be flattened and notched like a file for not quite half its length. This 

 vein, when the wings are expanded, rests on another projecting vein on 

 the hinder wing, in such a manner that when the upper wing is moved 

 the notched vein rubs over this vein as the bow rubbed with rosin works 

 on the violin string. 



Let any one now take a dried specimen of this butterfly from the cabi- 

 net and grasping the fore wing by its front edge rub it backwards and 

 forwards over the hinder one, so that the bases meet, but being at the 

 same time careful not to crumple the wings and so produce a false sound. 

 He will then without fail hear the sweet secrets of antiopa^ which are 

 beautiful and delicate in expression, recalling the trickle of the brooklet. 



I may notice that the Vanessa butterflies are renowned and well- 

 known as stridulators on account of their large size, bat that nearly all 

 butterflies rub their wings together when under the influence ot the 

 emotion of love, and since it is the result of friction to produce a striated 

 surface, many of these smaller ones must have organs of sound too fine 

 for human sense. My own researches have always been circumscribed 

 from a want of adequate microscopic power. 



