Once a Week (magazine)/Series 1/Volume 3/The glow-worm
Amongst the several luminous insects of this country, the Glow-worm is undoubtedly the most interesting. Who that has walked along shady lanes, and in woodland scenery, where these insects abound, on a calm, warm summer’s evening, but has been delighted with the effulgence of these creatures, sparkling like little stars of earth, and glowing like night-tapers with beauty? Shakespeare, with his wonderful knowledge of nature, has not failed to observe that as morning approached, the light of the Glow-worm was extinguished—
The glow-worm shows the matin to be near,
And ’gins to pale his ineffectual fire.
The poet Waller also described the same fact. He supposes a man to have found a glow-worm for the first time, and thinks he possessed himself of—
A moving diamond, a breathing stone;
For life it had, and like those jewels shone:
He held it dear, ’till, by the springing day
Informed, he threw the worthless grub away.
But let us inquire a little into its natural history, and this will not be found without its interest. Some doubts have occurred as to the food of the glow-worm. From actual observation, it has been ascertained that its larvæ feed on snails, decayed worms, &c., and are decidedly carnivorous. Neither old nor young touch plants as food. The larvæ are very voracious in their habits; but it is supposed that the perfect insect eats but little. If it does eat, it probably feeds on animal substance.
The female is without wings, and is far more luminous than the male. She may sometimes be found crawling up a blade of grass, to make herself more conspicuous, and in order—
To captivate her favourite fly,
And tempt the rover through the dark.
The males have wings, and may be seen hovering over the females in twilight. The male is a dusky, slender scarabæus. The females have the power of extinguishing or concealing their light: and Mr. White of Selborne thinks that they put it out altogether between eleven and twelve every night, and shine no more that evening. This wise provision of nature may probably be for the purpose of preventing their being preyed upon by nocturnal birds. Indeed, it has been supposed that nightingales feed on them; and certainly the favourite haunts of these birds are often in localities where glow-worms abound. It may be mentioned that as soon as the female has deposited her eggs (which by the way shine in the dark), the light disappears in both sexes.
Persons who eat peaches, apricots, and other stoned fruit (and who does not?) may often find a little centipede about an inch and a half, or two inches long, curled up in the centre of the fruit. This insect, if placed in a glass, and looked at when it is dark, will be found to be considerably luminous. Blumenbach asserts that another luminous insect gives such a strong light, that two of them placed in a glass, gave sufficient light to read by. The fire-flies of hot countries have wings, both male and female; so that when they occur in great quantities, they exhibit a brilliant spectacle to the inhabitants. That pest of farmers, the wire-worm, is, we believe, luminous.
Messrs. Kirby and Spence give an interesting account of the Blater noctilucus, with which we will conclude this article. This insect has the luminous property in a very high degree. It is an inch long, and about one third of an inch broad. It gives out its principal light from two transparent eye-like tubercles placed upon the thorax; but it has also two luminous patches concealed under the wings, which are not visible except when the insect is flying, at which time it: appears with fine brilliant gems of the most beautiful golden-blue lustre. In fact, the whole body is full of light, which is so considerable, that the smallest print may be read by moving one of these insects along the lines. In the West Indies, and particularly in St. Domingo, where they are very common, the natives employ these living lamps instead of candles, in performing their evening household occupations. Southey has introduced this insect in his “Madoc,” as furnishing the lamp by which Coatel rescued the British hero from the hands of the Mexican priests:—
She beckon’d and descended, and drew out
From underneath her vest a cage, or net
It rather might be call’d, so fine the twigs
Which knit it, where, confined, two fireflies gave
Their lustre. By that light did Madoc first
Behold the features of his lovely guide.