The Insect World. Figuier Louis
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anterior limbs are separated from the others, and are inserted nearly under the head; the posterior ones are particularly large and strong.
The jumps which fleas are able to make are really gigantic, and the strength of these little animals quite herculean, when compared with the size of their bodies. The reader may be inclined to smile at the assertion that the flea possesses herculean strength; but let him wait a little, and he will find that it is no exaggeration.
To give some idea of the strength, the docility, and the goodwill of the fleas, some wonderful little things have been made, which have served at the same time to show the astonishing skill of certain workmen.
In his "Histoire abrégée des Insectes," published in the seventh year of the French Republic, Geoffroy relates that a certain Mark, an Englishman, had succeeded, by dint of patience and art, in making a gold chain the length of a finger, with a padlock and a key to fasten it, not exceeding a single grain in weight. A flea attached to the chain pulled it easily. The same learned writer relates a still more surprising fact. An English workman constructed a carriage and six horses of ivory. The coachman was on the box, with a dog between his legs, there were also a postillion, four persons in the carriage, and two servants behind, and the whole of this was drawn by one flea.
In his "Histoire Naturelle des Insectes Aptères," Baron Walckenaer relates the following marvellous instance of industry, patience, and dexterity:—
"I think it is about fifteen years ago, that the whole population of Paris could see the following wonders exhibited on the Place de la Bourse for sixty centimes. They were the learned fleas. I have seen and examined them with entomological eyes, assisted by a glass.
"Thirty fleas went through military exercise, and stood upon their hind legs, armed with pikes, formed of very small splinters of wood.
"Two fleas were harnessed to and drew a golden carriage with four wheels and a postillion. A third flea was seated on the coach-box, and held a splinter of wood for a whip. Two other fleas drew a cannon on its carriage; this little trinket was admirably finished, not a screw or a nut was wanting. These and other wonders were performed on polished glass. The flea-horses were fastened by a gold chain attached to the thighs of their hind legs, which I was told was never taken off. They had lived thus for two years and a half, not one having died during the period. To be fed, they were placed on a man's arm, which they sucked. When they were unwilling to draw the cannon or the carriage, the man took a burning coal, and on it being moved about near them, they were at once roused, and recommenced the performances."
The learned fleas were the admiration and amazement of Paris, Lyons, and the chief provincial towns of France, in 1825.
But how, one will ask, was it possible in a large public room to see this wonderful sight? And it is necessary that this should be explained. The spectators were seated in front of a curtain, provided with magnifying glasses, through which they looked, as they would at a diorama of landscapes or buildings.
But let us return to the natural history of our insect. The female flea lays from eight to twelve eggs, which are of oval shape, smooth, viscous, and white.
Contrary to what one might think, à priori, the flea does not fix its eggs to the skin of its victims. She lets them drop on the ground, between the boards of floors, or old furniture, and among dirty linen and rubbish.
M. Defrance has remarked that there are always found mixed with the eggs a certain number of grains of a brilliant black colour, which are simply dried blood. This is a provision which the foreseeing mother has prepared at our expense to nourish her young offspring.
In four or five days in summer, and in eleven days in winter, one may see coming out of these eggs small, elongated larvæ, of cylindrical form, covered with hair, and divided into three parts, the last provided with two small hooks. The head is scaly above, has two small antennæ, and is without eyes. These larvæ are without limbs, but they can twist about, roll themselves over and over, and even advance pretty fast by raising their heads. Though at first white, they become afterwards of a reddish colour.
About a fortnight after they are hatched they cease to eat, and are immovable, as if about to die. They then commence to make a small, whitish, silky cocoon, in which they are transformed into pupæ. In another fortnight these pupæ become perfect insects.
A most remarkable trait, and unique among insects, has been observed in the flea. The mother disgorges into the mouths of the larvæ the blood with which she is filled.
The flea is most abundant in Europe and the North of Africa. Certain circumstances particularly favour its multiplication; being most abundant in dirty houses, in barracks, and in camps; in deserted buildings, in ruins, and in places frequented by people of uncleanly habits.
Other kinds of fleas live on animals, as, for example, the cat flea, the dog flea, and those of the pigeon and poultry.
We shall say a few words about a peculiar species which abounds in all the hot parts of America, but principally in the Brazils and the neighbouring countries. This formidable species is the Chigo (Pulex penetrans).
The chigo, called also the tick, is smaller than the common flea. It is flat, brown with a white spot on the back, and is armed with a strong pointed stiff beak, provided with three lancets. It is with this instrument that the female attacks man with the intention of lodging in his skin and bringing forth her young there.
The chigo attacks chiefly the feet. It slips in between the flesh and the nails, or gets under the skin of the heel. Notwithstanding the length of the animal's beak, introducing itself beneath the skin does not at first cause any pain; but after a few days one is made aware of its presence by an itching, which, though at first slight, gradually increases, and ends by becoming unbearable.
The chigo, when under the skin, betrays itself by a bump outside. Its body has now become as large as a pea; in the attacked skin a large brown bag containing matter is formed. In this bag are collected the eggs, which issue from an orifice in the posterior extremity, and are not hatched in the wound itself, as was long thought to be the case.
The chigoes are an object of terror to the Brazilian negroes. These formidable parasites sometimes attack the whole of the foot, which they devour, and thus bring on mortification; many negroes losing the bones of some of their toes by the ravages of these dangerous creatures. To guard against their attacks, they wear thick shoes, and examine their feet carefully every day. The plan usually followed in the Brazils to prevent the chigoes from injuring the feet, is to employ children, who, by their sharpness of sight, can easily perceive the red spot on the skin where the chigo has entered. These children are in the habit of extracting the insect from the wound by means of a needle. But this is not without risk; as, if any portion of the insect remains in the wound, a dangerous inflammation may ensue. For this reason, operators who are renowned for their skill are much sought after, flattered, and rewarded by the poor negroes of the plantations.
The Head Louse (Pediculus capitis, Fig. 18) is an insect with a flat body, slightly transparent, and of greyish colour, spotted with black on the spiracles, soft in the middle, and rather hard at the sides. The head, which is oval, is furnished with two thread-like antennæ, composed of five joints, which are constantly in motion while the creature is walking; it is also furnished with two simple, round, black eyes; and lastly, with a mouth. In the front of the head is a short, conical, fleshy nipple. This nipple contains a sucker, or rostrum, which the animal can put out when it likes, and which, when extended, represents a tubular body, terminating in six little pointed hooks, bent back, and serving to retain the instrument in the skin. This organ is surmounted by four fine hairs, fixed to one another, and seated in its interior. It is by means of this complicated apparatus that the louse pricks and sucks the skin of the head. The thorax is nearly square, and divided into three parts by deep incisions. The abdomen, strongly lobed at the sides, is composed of eight rings, and is provided with sixteen spiracles.