92 BUTTERFLY SOUNDS 



" produced a most curious crackling or rustling 

 noise," which " was evidently emitted at the crea- 

 ture's will, and was distinctly audible within two 

 or three yards of the insect." Fritz Miiller, who 

 adds his testimony to the clicking sound emitted 

 by Ageronia, states that quite another butterfly, 

 a species of Eunica, equally produces the noise, 

 and he also heard a sound, even louder than that 

 made by Ageronia, " produced by two small 

 brown butterflies which I did not succeed in 

 catching." 



The sounds made by butterflies of the temper- 

 ate zone and compared by nearly all observers to 

 that of the abrasion of one rough surface upon 

 another, more or less faint, would hardly seem at 

 first sight to be entirely analogous to the clicking 

 sounds made by their more noisy brethren of the 

 tropics, but it is not impossible that they should 

 be. Experiments made after death upon the 

 Green Comma (Polygonia faunus) show that they 

 must be capable of producing the same sounds as 

 the Mourning Cloak (Euvanessa antiopa) ; and 

 in this connection, an instance which occurred to 

 me one summer on the top of Mt. Washington 

 has a direct bearing ; for while walking on the 

 carriage road, I started up a pair of the former, 



