“For see, the glow-worm lights her amorous fire!”[[148]]
on which one of his editors of the nineteenth remarks: “This is still the generally received notion, but the fact is that both sexes of the glow-worm are phosphorescent, not only in the perfect insect, but also in the larva and even pupa state.”[[147]] But this does not affect White’s statement, which is the simple fact, as well as “the generally received notion,” and, moreover, though our own male glow-worm is phosphorescent, it is not so brilliantly so as the female. Indeed, in the ninth edition of the Encyclopædia Britannica—which is later than this editorial note—it is stated not to be so at all, so that even if White believed this—which is not very clear—he has been supported by learned authority for a very long time.
In other species the male is the more brilliant, or the sexes do not differ greatly in this respect, each one lighting its “amorous fire” in the degree that nature allows it to—as no doubt our own male does too. Of this fact, which, in the light of Darwinism, might have been boldly assumed, there is no longer any doubt after Professor Emery’s interesting observations[[149]] on the Italian species Luciola Italica. These were made in the meadows around Bologna, where, having caught some females, the Professor imprisoned them in glass tubes and laid them down amidst the grass. In this situation, though smell as an attractive agent was excluded, males would come flashing to the glass, and, on the other hand, as soon as the lamp of any of these became visible, the female would kindle her own, if it had previously been unlighted. Arrived on the spot, the male would dash madly about the unapproachable female, who continued to light her lamp at him till another, and then others, arrived, when it is to be supposed that her favours were distributed. In the end there would sometimes be a dozen fiery rivals glowing and flashing round the tube. But though the female shot out her attractive beams with evident intent to please, it does not appear that she was the seeker in the business, since we hear only of males flying to the imprisoned females, and not of females pursuing these males. To such modest merit, therefore, as a nice distinction between different ways of attaining the same end may entitle her, the female glow-worm also is entitled.
The light of the two sexes in the Italian glow-worm is described by Professor Emery as being the same in colour and intensity, but differing in some other respects. The flashes of the male, for instance, are more quickly recurrent, whilst those of the female gleam out at longer intervals, but last for a longer time. They are, also, more tremulous, as well as more restricted, though what is meant by this last expression, since the brightness is said to be equal, is not quite apparent. Possibly it may imply that the light proceeds from a lesser area of the body, but, if so, this should be clearly stated, even in a résumé. I can find no reference to such a fact, if it be one, in the text-books.
From the above it is evident that the glow-worm’s fires are anything but “uneffectual” from the point of view of the insect, but Shakespeare was no doubt thinking of something very different—their paling, namely, before the light of dawn. According to Gilbert White, however, they should have been out long ago—the glow-worm being too wise to afford opportunities of comparison in this respect. Thus subtly does the naturalist of Selborne impugn the accuracy of the Bard of Avon: “By observing,” he says, “two glow-worms which were brought from the field to the bank in the garden, it appeared to us that these little creatures put out their lamps between eleven and twelve, and shine no more for the rest of the night.”[[149]] The intention here, though cleverly disguised, is not sufficiently so to escape detection. It was possibly seen through by the late Charles and Mary Cowden Clarke, who in one of the million or so notes to their edition of Shakespeare, say, without distinct reference to the passage in question:—“Uneffectual. There is double signification included in this word; it means the glow-worm’s light, which shines without giving heat, and which no longer shows when morning appears.”[[150]] Thus whilst not committing themselves to White’s opinion they provide a safe refuge for their author, in case it should prove in time to be correct; according to the sound principle contained in a Russian proverb which says, “Had he known where he was going to fall, he would have laid down straw.”
In tropical countries fire-flies take the place of glow-worms with us, and though the light which these give out is not so soft and poetic as the lovely green or golden green one of the latter, yet it is more effectively beautiful, owing to the way in which it wanders through the night, appearing and disappearing in successive brilliant flashes. For here the beetle that carries the lamp is a flier, and flashes it about at pleasure through the air, having the power, it would seem, either of showing or concealing its light. The effect of a number of these points of brilliancy, gleaming out, now here, now there, on the soft night air of the tropics, is inexpressibly beautiful, as though, in a smaller firmament, innumerable miniature stars had ceaseless birth and death.
Women, who like to emphasise their own beauty, or the want of it, by placing themselves in juxtaposition with every lovely thing in nature, and care not if a thousand deaths go to help one smile or glance, have not forgotten the fire-flies. They put them in their hair, or wire them onto their dresses, threading them together, sometimes, in long bands, which they wind about their fair—or otherwise—persons; they do this, more especially, when going out to parties, fancy-dress balls, or other social entertainments. The advantages are obvious, for the homeliest features may be thus lighted up, and the dullest woman become brilliant. No wonder that in some South American cities—Vera Cruz for example—these fire-fly beetles form quite an important article of trade, all for toilette purposes.[[151]] The natives catch them by waving sticks with burning coals tied to their ends through the air, by the light of which they are attracted, and so come within reach of a long-handled butterfly net. When caught, they are put into a box covered with a little netting of wire, and there kept till wanted. They are fed upon sugar-cane, and twice a day must be bathed in tepid water.[[151]]
What is done with the poor beetles after they have contributed to the night’s amusement we are never told—whether those that have been all wired together are unwired and let go, or pulled off in two or more pieces to save trouble, as seems more likely. It is likelier still perhaps, in the houses of the rich, that the whole thing is flung aside, and the poor living lamps left to struggle till they die—unprovided with sugar-cane. But such details are not thought worth mentioning. The charming effect is the one thing dwelt upon, and charming it may very well be, though to gain it through a mass of even insect discomfort is, to my mind, a contemptible thing. Fancy fifty or a hundred uncomfortable, writhing, struggling things on the dress that a lady is dancing in, every one of which, if let go, would make a wandering star in the air more really worth looking at than the whole ball-room together! By substituting flowers for women, however, effects far more beautiful are gained through less reprehensible means. The fire-beetles—why should they be called flies?—are in this case confined in small globes of delicate glass, set amidst clusters of flowers, or flowering shrubs, and thus they softly illuminate the garden. Give them some sugar-cane whilst the party is in progress, and let them go next morning, and they will have had very little to complain of—a strange experience for any lower creature that gets into the clutches of the highest one.
The most wonderful of all the fire-beetles is the large one of near two inches long—quite, or more, if we count the antennæ—that inhabits Mexico, where in ancient times it was used as a lantern by the Aztecs in their night-journeys, as it still is by their modern descendants. It is wonderful, not by reason of its size merely, or, in any special degree, of the light it emits—though this is brilliant in proportion to it—but because it carries three separate lamps: two above, situated on either side of the thorax, and one on the under side, just in front of the abdomen. Thus, as it turns or varies in its flight, one flash of the most intense brilliancy follows another, like the revolving light of a lighthouse. The colour of the light is described as a rich green—richest, however, or at least brightest, on the under surface.[[151]] The beauty and dazzling effect of this upon a dark night can be imagined, and is thus described by Dr. Kidder: “Before retracing my steps I stood for a few moments looking down into the Cimmerian blackness of the gulf before me; and while thus gazing a luminous mass seemed to start from the very centre. I watched it as it floated up, revealing in its slow flight the long leaves of the palm Euterpe edulis, and the minuter foliage of other trees. It came directly towards me, lighting up the gloom around with its three luminosities, which I could distinctly see.”[[151]] There is something wonderfully poetical in the thought of winged beings like this pursuing each other through the night, by the light of these glorious flashes—the “light of their own loveliness,” it may well be called, since it is, indeed, their beauty. If seems curious and a waste that where there is the greatest capacity of poetic imagination we should find the least, or almost the least, realisation of it in habit and structure.
We know from Oviedo that the Mexican Indians, when they travelled at night, were accustomed to fasten these great refulgent beetles on their hands and feet, and thus pass flaming through the country. They danced, too, by their light, and even wove or painted by it. Why, therefore, could not lamps of great power, as well as beauty, be evolved from such insects by bringing the selective agency of man to bear upon them? The phosphorescent principle in living nature has not perhaps been made the most of by us. Was more made of it by the Aztecs? and did they turn their attention to the systematic rearing of these living lamps?—for, from hearing so little about them one would not think that these insects were so useful now, as, from the above account and what other contemporary Spanish writers tell us, it would seem that they were, at the time of this old and cruelly destroyed civilisation.