1927] 
The Reaction of Datana Larvce to Sounds 
129 
THE REACTION OF DATANA LARVAE TO SOUNDS. 
By Cyril E. Abbott, 
Zoological Laboratories, Johns Hopkins University. 
A considerable amount of discussion has been devoted to 
the possibility of the presence of an auditory sense in insects. 
Unfortunately, much of this discussion has been purely theo- 
retical. At one time it was generally supposed that all or most 
insects could hear. This argument was based upon two facts: 
the possession, by insects, of sensory organs which have a struc- 
ture indicating a possible auditory function, and the insect 
production of sounds. For what other purpose, it was argued, 
can stridulating organs be used, if not for that of impressing 
other insects? 
Fabre fired two mortars in close proximity to a number of 
Cicadse without affecting their songs. He concludes, “If any 
one were to tell me that the Cicadse strum on their noisy ins- 
truments without giving a thought to the sound produced and 
for the sheer pleasure of feeling themselves alive, just as we rub 
our hands in a moment of satisfaction, I should not be greatly 
shocked.” Lutz (1926) is of the same opinion. He writes: 
“When we can explain the purpose of a man’s snoring or the 
rattling of a Ford car, we may know why this beetle grub rasps. 
Having slept with a man that snored and having driven a Ford, 
I believe that the sounds in question are unintentional and quite 
incidental to the structure of the man and of the machine. May 
not the same be true of the beetle grub?” 
In spite of such incomplete considerations of the subject, 
there is evidence that certain insects have an auditary sense. 
Radi (1905), arguing in part from structure, and in part 
from experiment, concludes that insects have auditory powers of 
a primitive and limited kind. 
In 1914 Turner and Shwarz tested the auditory powers of 
various Catacola moths, and found that from 80 to 100 percent 
of the insects gave positive responses to notes of the pitches C,4 
A, 4 and B4 from a Galton whistle. In the same year Turner 
