INDIRECT INJURIES CONCLUDED.
I have not yet arrived at the end of my catalogue of noxious insects. I have introduced you, indeed, to those that annoy man in his own person, in his domestic animals, in the produce of his fields, gardens, orchards, and forests; in a word, in every thing that is endued with the vital principle: but I have as yet said nothing of the injuries which he receives from them in that part of his property, consisting either of animal or vegetable matter, from which that principle is departed. And with these I shall conclude this melancholy detail of evils inflicted upon us by the very animals I am enticing you to study. The rest of my correspondence, I flatter myself, will paint them in more inviting colours.
The insects to which I now allude may be divided into those that attack and injure our food, our drugs and medicines, our clothes, our houses and furniture, our timber, and even the objects of our studies and amusements.
Various are those that attempt to share our food with us. Flour and meal are eaten by the grub of Tenebrio Molitor, best known by the name of the meal-worm, which will remain in it two years before it goes into its state of inactivity:—its ravages however are not confined to flour alone, for it will eat any thing made of that article, such as bread, cakes, and the like. Old flour is also very apt to be infested by a mite (Acarus Farinæ)[405]. In long voyages the biscuit sometimes so swarms with the weevil and another beetle (Dermestes paniceus, L.) that they are swallowed with every mouthful; and even the ground peas so abound with these little vermin, that a spoonful of soup cannot be taken free from them[406]. Bread is also devoured by Trogosita caraboides, a larger beetle before alluded to[407].
Every one is aware that our animal food suffers still more than our farinaceous from insects; but perhaps you would not expect that our hams, bacon, and dried meats should have their peculiar beetle. Yet so it is; and this beetle, (Dermestes lardarius,) when a grub, sometimes commits great devastation in them; as does that of another described by De Geer under the name of Tenebrio lardarius[408]. How much our fresh meat of all kinds, our poultry and fish, are exposed to the flesh-fly, whose maggots will turn us disgusted from our tables, if we do not carefully guard these articles from being blown by them, you well know;—and assailants more violent, hornets, wasps, and the great rove-beetle, (Creophilus maxillosus) if butchers do not protect their shambles, will carry off no inconsiderable portion of their meat. A small cock-roach (Blatta lapponica) which I have taken upon our eastern coast, swarms in the huts of the Laplanders, and will sometimes annihilate in a single day, a work in which a carrion-beetle (Silpha lapponica) joins, their whole stock of dried fish[409]. The quantity of sugar that flies and wasps will devour, if they can come at it, especially the latter, the diminutive size of the creatures considered, is astonishing:—in one year long ago, when sugar was much cheaper than it is now, a tradesman told me he calculated his loss, by the wasps alone, at twenty pounds. A singular spectacle is exhibited in India (so Captain Green relates) by a small red ant with a black head. They march in long files, about three abreast, to any place where sugar is kept; and when they are saturated, return in the same order, but by a different route. If the sugar, upon which they are busy, be carried into the sun, they immediately desert it. What is very extraordinary, these ants are also fond of oil. Sweetmeats and preserves are very subject to be attacked by a minute oblong transparent mite with very short legs and without any hair upon its body. Our butter and lard are stated to be eaten by the caterpillar of a moth (Aglossa pinguinalis). Tyrophaga[410] Casei, the parent fly of the jumping cheese-maggot, loses no opportunity, we know, of laying its eggs in our fresh cheeses, and when they get dry and old the mite (Acarus Siro) settles her colonies in them, which multiply incredibly. Other substances, more unlikely, do not escape from our pygmy depredators. Thus Reaumur tells us of a little moth whose larva feeds upon chocolate, observing very justly that this could not have been its original food[411]. Both a moth and a beetle (Sylvanus frumentarius?) were detected by Leeuwenhoek preying upon two of our spices, the mace and the nutmeg[412]. The maggots of a fly (Oscinis cellaris) are found in vinegar, in the manufactories of which the perfect insects swarm in incredible numbers; others I have found in wine, which turned to a minute fly, of a yellow colour, with dark eyes and abdomen, which though near Anthomyia as to its wings, appears to belong to a distinct genus not published by Meigen, which in my MS. stands under the name of Oinopota ventralis; and sometimes even water in the casks of ships, in long voyages, so abounds with larvæ of this tribe as to render it extremely disgusting. Browne, in his History of Jamaica, mentions an ant (Formica omnivora, L.) probably belonging to Myrmica, that consumes or spoils all kinds of food; which perhaps may be the same species that has been observed in Ceylon by Percival, and is described by him as inhabiting dwelling-houses, and speedily devouring every thing it can meet with. If at table any one drops a piece of bread, or of other food, it instantly appears in motion as if animated, from the vast number of these creatures that fasten upon it in order to carry it off. They can be kept, he tells us, by no contrivance from invading the table, and settling in swarms on the bread, sugar, and such things as they like. It is not uncommon to see a cup of tea, upon being poured out, completely covered with these creatures, and floating dead upon it like a scum[413].
In some countries the number of flies and other insects that enter the house in search of food, or allured by the light, is so great as to spoil the comfort of almost every meal. We are told that during the rainy season in India, insects of all descriptions are so incredibly numerous, and so busy every where, that it is often absolutely necessary to remove the lights from the supper-table:—were this not done, moths, flies, bugs, beetles, and the like, would be attracted in such numbers as to extinguish them entirely. When the lights are retained on the table, in some places they are put into glass cylinders, which St. Pierre tells us is the custom in the Island of Mauritius[414]; in others the candlesticks are placed in soup-plates, into which the insects are precipitated and drowned. Nothing can exceed the irritation caused by the stinking bugs when they get into the hair or between the linen and the body; and if they be bruised upon it the skin comes off[415]. To use the language of a poet of the Indies, from whom some of the above facts are selected,
"On every dish the booming beetle falls,
The cock-roach plays, or caterpillar crawls:
A thousand shapes of variegated hues
Parade the table and inspect the stews.
To living walls the swarming hundreds stick,
Or court, a dainty meal, the oily wick;
Heaps over heaps their slimy bodies drench,
Out go the lamps with suffocating stench.
When hideous insects every plate defile,
The laugh how empty, and how forced the smile[416]!"
Drugs and medicines also, though often so nauseous to us, form occasionally part of the food of insects. A small beetle (Sinodendrum pusillum[417]) eats the roots of rhubarb, in which I detected it in the East India Company's warehouses. Opium is a dainty morceau to the white ants[418];—and, what is more extraordinary, Anobium paniceum[419] (a coleopterous insect that preys naturally upon wood) has been known to devour the blister-beetle.—Swammerdam amongst his treasures mentions "a detestable beetle," produced from a worm that eats the roots of ginseng; and he likewise notices another, the larva of which devours the bag of the musk[420].—The cochineal at Rio de Janeiro is the prey of an insect resembling an Ichneumon, but furnished with only two wings; its station is in the cotton that envelops the Coccus. Previous to its assumption of the pupa it ejects a large globule of pure red colouring matter[421]. And lastly, the Coccus that produces the lac (C. Lacca) is, we are told, devoured by various insects[422].
Perhaps you imagine that these universal destroyers spare at least our garments, in which you may at first conceive there can be nothing very tempting to excite even the appetite of an insect. Your housekeeper, however, would probably tell you a different story, and enlarge upon the trouble and pains it costs her to guard those under her care against the ravages of the moths. Upon further inquiry you would find that nothing made of wool, whether cloth or stuff, comes amiss to them. There are five species described by Linné, which are more or less engaged in this work: Tinea vestianella, tapetzella, pellionella, Recurvaria sarcitella, and Galleria Mellonella. Of the first we have no particular history, except that it destroys garments in the summer; but of the others Reaumur has given a complete one. T. tapetzella, or the tapestry moth, not uncommon in our houses, is most injurious to the lining of carriages, which are more exposed to the air than the furniture of our apartments. These do not construct a moveable habitation like the common species, but, eating their way in the thickness of the cloth, weave themselves silken galleries in which they reside, and which they render close and warm by covering them with some of the eroded wool[423]. T. pellionella is a most destructive insect, and ladies have often to deplore the ravages which it commits in their valuable furs, whether made up into muffs or tippets—it pays no more respect to the regal ermine than to the woollen habiliments of the poor; its proper food, indeed, being hair, though it devours both wool and fur. This species, if hard pressed by hunger, will even eat horsehair, and make its habitation, a moveable house or case, in which it travels from place to place, of this untractable material. These little creatures will shave the hair from a skin as neatly and closely as if a razor had been employed[424].—The most natural food of the next species, R. sarcitella, is wool; but in case of necessity it will eat fur and hair. To woollen cloths or stuffs it often does incredible injury, especially if they are not kept dry and well aired[425]. Of the devastation committed by Galleria Mellonella in our bee-hives I have before given you an account: to this I must here add, that if it cannot come at wax, it will content itself with woollen cloth, leather, or even paper[426]. Mr. Curtis found the grub of a beetle (Ptinus Fur) in an old coat, which it devoured, making holes and channels in it; and another insect of the same order (Megatoma Pellio), Linné tells us, will sometimes entirely strip a fur garment of its hair[427]. A small beetle of the Capricorn tribe (Callidium pygmæum) I have good reason to believe devours leather, since I have found it abundant in old shoes.