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extreme tip, the curvature being always downward. This tube 
appears to be composed’ of two pieces, one being protruded from 
within the other. If the pressure be very strong, there comes 
out at last from the end of the tube two long cartilaginous 
filaments, blunt at the extremity, which the insect sports witb. 
during the continuance of the pressure, causing first one and then 
the other to come out more or less from the sheath. The total 
length of this apparatus, tube and filaments together, when fully 
exserted, exceeds the length of the whole body of the insect. 
There is no doubt, De Geer thinks, it is the conduit by which 
the ova are introduced perhaps into the cracks of the wood on 
which the larve are to feed. 
It is not so easy to find a use for the strangely long antenne 
of this insect, which De Geer says look as if they must be an 
incumbrance to it. He supposes they have their use, but he does 
not pretend to say what the use is. In truth, however, we 
know but very little of the purposes served by the antenne of 
- insects generally. Some have supposed them to be organs of 
hearing ; others of smell; more often, and perhaps more rightly, 
they have been considered as feelers, or organs of touch. In the 
case of ants, whatever may be the case of other insects, Mr. 
Romanes observes that “the antenne appear to be the most 
important of the sense-organs, as their removal produces an 
extraordinary disturbance in the intelligence of the animal.”* 
It is difficult also to explain why they should be so much more 
developed in some insects than in others. Many insects have the 
_antennz extremely short, in some cases scarce any that are 
discernible. These differences may depend upon differences of 
habits in the insects themselves. And there is one circumstance 
which may lead us a little way towards an answer to this inquiry ; 
namely, the differences often observable in the two sexes, not only 
in the length—but also in the structure—of the antennz. In 
the insect before us, the antennz of the male are almost always 
* “ Animal Intelligence,” p. 142. 
