SENSES OF INSECTS. 253 
engaged in absorbing honey might be touched in every 
other part without being disturbed. He seized several 
of them, forced them to unfold their proboscis, and then 
stopped their mouth with paste. When this was become 
sufficiently dry to prevent their getting rid of it, he re- 
stored to them their liberty: they appeared not incom- 
moded by being thus gagged, but moved and respired 
as readily as their companions. He then tempted them 
with honey, and presented to them near the mouth, oil 
of turpentine, and other odours that they usually have 
an aversion to; but all produced no sensible effect upon 
them, and they even walked upon the pencils saturated 
with them?. 
These experiments incontestibly prove that the organ of 
scent in bees—and there is no reason to think that other 
insects do not follow the same law—is in or near the 
mouth, and above the proboscis. It remains, therefore, 
that we endeavour to discover its precise situation: and 
as insects cannot tell us, nor can we perceive by their 
actions, in what precise part the sense in question resides, 
the only modes to which we can have recourse to form 
any probable conjecture, are analogy and dissection. At 
first, the opinion noticed above, that the palpi are its or- 
gans, seems not altogether unreasonable; but as the ar- 
gument from analogy, except as to their situation near 
the mouth, is not in favour of them, and there seems no 
call, were smell their function, for the numerous variations 
observable in their structure, I think we must consider 
them, as I have endeavoured to prove, rather as instru- 
~ ments of touch. Let us now inquire, whether there be 
* Huber Abeilles 1. 375 —. 
