198 THE VOICE OF ATROPOS 



worms are not gregarious ; if they were so, there would be 

 preeious little profit to farmers in growing potatoes. One 

 caterpillar can seldom be within earshot of another, and 

 it takes two to make a conversation or a quarrel. No ; 

 without denying that Acherontia may be gifted in this 

 peculiar way for purposes of communication with his 

 own kind, I cannot help thinking that the faculty is 

 mainly protective. It adds to the uncanny character of 

 the creature, inducing possible aggressors to give it a 

 wide berth, and serving a like purpose to the curious horn 

 which the caterpillars of all the Sphingidce, or hawk-moths, 

 whereof the death's-head is the chief, bear on their 

 posterior extremity. This horn, absolutely futile as a 

 weapon of offence, looks like one, and thus serves as an 

 instrument of defence. 



Doubtless there be many sounds uttered by humble 

 creatures inaudible to human ears, but easily heard by 

 other animals. Many people cannot hear the squeak of a 

 bat; there is no chord in their cochlea which responds 

 to such a high note. A friend of mine, quick in hearing 

 ordinary sounds, sits quite unconscious though the air 

 resounds with the incessant chirping of cicadas, and he 

 cannot hear the call of a partridge. I have a hazy recol- 

 lection of one of Grimm's fairy-tales, in which a boy is 

 described as being suddenly endowed with the power of 

 hearing and understanding the language of all living 

 creatures. If I remember right, he found the conversa- 

 tion in an ant-hill peculiarly intellectual. Even so ; every 

 flying, creeping, or swimming thing might have its 

 message for us had we but ears to hear. The hearing of 

 few persons is so gross as to miss the accents of the 

 death's-head moth ; as to the meaning thereof, I have an 



