DEAXn’S-nEAD aA-WTC-MOTH. 137 
sible, from the nature of their organization, that 
any insect can he possessed of a genuine voice, it 
has been conjectured that the noise is occasioned hy 
the friction of one organ against another, as is well 
kno'wn to be the case ■with many beetles, grass- 
hoppers, &c. Reaumur and others accordingly 
ascribe it to the reciprocal action of the trunk and 
palpi ; but the sound having been found to continue 
after these organs were cut off, it must evidently 
have some other origin. Under the idea that it 
was connected with the motion of the wings, 
another observer was led to conceive that its source 
was two concave scales placed at the base of these 
appendages, against which the air is forcibly pro- 
pelled by their rapid motion. M. Lorey, a French 
physician, maintains that the stridulation in question 
is produced by the escape of air from a trachea 
placed on each side of the base of the abdomen, 
which, when the animal is in a state of repose, are 
closed by a fascicle of fine hairs. A more recent 
writer, M. Duponchel, controverts all these state- 
ments, and gives it as his opinion that the noise is 
emitted from the intenor of the head, in which there 
is a cavity communicating with the trunk, and near 
which are placed the muscles by which the latter is 
put in motion. As M. Lorey, however, affirms that 
he has heard the sound after the head was ampu- 
tated, and M. Duponchel makes the same assertion 
in relation to the abdomen, these various opinions 
must be considered as irreconcilable, and the matter 
left to be decided by future investigation. 
