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Fig. 45.—Antenna of Talarocera nigripennis, ♂.—After Williston.

Recent examination of the sense-organs in the antennæ of an ant, wasp, or bee enables us, he says, to realize what wonderful organs the antennæ are. In such insects we have a rod-like tube which can be folded up or extended out into space, containing the antennal nerve, which arises directly from the brain and sends a branch to each of the thousands of olfactory pits or pegs which stud its surface. The antenna is thus a wonderfully complex organ, and the insect must be far more sensitive to movements of the air, to odors, wave-sounds, and light-waves, than any of the vertebrate animals.

That ants appear to communicate with each other, apparently talking with their antennæ, shows the highly sensitive nature of these appendages. “The honey-bee when constructing its cells ascertains their proper direction and size by means of the extremities of these organs.” (Newport.)

How dependent insects are upon their antennæ is seen when we cut them off. The insect is at once seriously affected, its central nervous system receiving a great shock, while it gives no such sign of distress and loss of mental power when we remove the palpi or legs. On depriving a bee of its antennæ, it falls helpless and partially paralyzed to the earth, is unable at first to walk, but on partly recovering the use of its limbs, it still has lost the power of coördinating its movements, nor can it sting; in a few minutes, however, it becomes able to feebly walk a few steps, but it remains over an hour nearly motionless. Other insects after similar treatment are not so deeply affected, though bees, wasps, ants, moths, certain beetles, and dragon-flies are at first more or less stunned and confused.