The flash was almost coinstantaneous in the two rings, but it was just perceptible first in the anterior one.

The shining matter was fluid and very adhesive: little spots, where the skin had been torn, continued bright with a slight scintillation, whilst the uninjured parts were obscured.

When the insect was decapitated the rings remained uninterruptedly bright, but not so brilliant as before: local irritation with a needle always increased the vividness of the light.

The rings in one instance retained their luminous property nearly twenty-four hours after the death of the insect.

From these facts it would appear probable, that the animal has only the power of concealing or extinguishing the light for short intervals, and that at other times the display is involuntary.