The gorgeous belts of the females, however, are very little, if at all, affected by even the most violent surprise. I fire a gun, for instance, beside a wire-gauze cage in which I am rearing a menagerie of female Glow-worms in the open air. The explosion produces no result: the illumination continues, as bright and placid as before. I take a spray, and rain down a slight shower of cold water upon the flock. Not one of my animals puts out its light; at the very most there is a brief pause in the radiance, and then only in some cases. I send a puff of smoke from my pipe into the cage. This time the pause is more marked. There are even some lamps put out, but they are soon relit. Calm returns, and the light is as bright as ever. I take some of the captives in my fingers and tease them a little. Yet the illumination is not much dimmed, if I do not press too hard with my thumb. Nothing short of very serious reasons would make the insect put out its signals altogether. All things considered, there is not a doubt but that the Glow-worm himself manages his lighting-apparatus, extinguishing and rekindling it at will; but there is one circumstance over which the insect has no control. If I cut off a strip of the skin, showing one of the luminous belts, and place it in a glass tube, it will shine away merrily, though not quite as brilliantly as on the living body. The presence of life is unnecessary, because the luminous skin is in direct contact with the air, and the flow of oxygen through the air-tube is therefore not required. In aerated water the skin shines as brightly as in the free air, but the light is extinguished in water that has been deprived of its air by boiling. There could be no better proof that the Glow-worm’s light is the effect of oxidisation. The light is white, calm, and soft to the eyes, and suggests a spark dropped by the full moon. In spite of its splendour it is very feeble. If we move a Glow-worm along a line of print, in perfect darkness, we can easily make out the letters one by one, and even words when they are not too long; but nothing is visible beyond this very narrow zone. A lantern of this kind soon tires the reader’s patience. These brilliant creatures know nothing at all of family affection. They lay their eggs anywhere, or rather strew them at random, either on the earth or on a blade of grass. Then they pay no further attention to them. From start to finish the Glow-worm shines. Even the eggs are luminous, and so are the grubs. At the approach of cold weather the latter go down into the ground, but not very far. If I dig them up I find them with their little stern-lights still shining. Even below the soil they keep their lanterns bravely alight. CHAPTER VI A MASON-WASP I HER CHOICE OF A BUILDING-SITE