United States or Pakistan ? Vote for the TOP Country of the Week !
If the Sphex's acts are so automatic as we are sometimes led to believe, in accordance with facts which are perfectly accurate, we ought always to observe the following succession of acts: first, hollowing of the burrow; second, the chase; third, the blows of the dart; fourth, the different manoeuvres for placing the victim in the sarcophagus.
In order not to interrupt the description and interfere with the succession of the acts, I have passed without remark the experiment in which Fabre substituted a living animal for the Sphex's already paralysed captive. It seems to me, however, that in this circumstance the insect showed judgment, and knew how to act in accordance with new requirements.
The Sphex's abdomen is agitated convulsively; the sting penetrates the skin, piercing a ganglion situated just beneath this point; the venom spreads and acts on the nervous cells, which can no longer convey messages to the muscles.
These habits being ascertained, Fabre proceeded to find out how the paralysis is produced. He awaited near a burrow the Sphex's arrival, dragging a victim by an antenna, and while the insect was occupied in the subterranean survey he substituted a living cricket for that which the Sphex had left, expecting to find it on the spot where it had been placed.
Word Of The Day