If some giddy-pate allow himself to be caught, will the Spider, at the distance whereto she has retired, be unable to take advantage of the windfall?
Never fear.

She arrives in a flash.

How is she apprised?
Let us explain the matter.
The alarm is given by the vibration of the web, much more than by the sight of the captured object.

A very simple experiment will prove this.
I lay upon a Banded Epeira's lime-threads a Locust that second asphyxiated with carbon disulphide.

The carcass is placed in front, or behind, or at either side of the Spider, who sits moveless in the centre of the net.