(From a beetle, to whose tribe it belongs). French flies, Muscae His-fianics, Spanish flies, cantharis major Meloe vesicato-rius, alatus viridissimus nitens, antennis nigris. Lin. Another kind is called Buprestis. In the system of La Treille the cantharis is separated from the genus meloe; and the insects with filiform horns, or antennae, half as long as the body, composed of eleven joints, are united into one family, styled the cantharidae. The genus cantharus contains twenty-two or twenty-three species. After the blistering cantharis, the most known are the c. dubia and Syria. Those in general use were formerly brought only from Spain, whence they were called Spanish flies; but they are met with in France, Italy, Germany, and other countries. Neumann says that they are ound chiefly in the spring season, and on poplar and ash trees; but they occur also on nut, rose, and other trees, whose leaves they devour; and when this food fails, they attack corn and grass, in which they make the most destructive ravages.
They are an insect of the beetle kind, known by their shining gold green colour, which is also of a bluish cast. They have a strong and sickly smell; when tasted they make no impression on the tongue at first, but presently an acrimony and pitchy flavour are perceived.
The largest and best are brought from Italy; they should be chosen fresh coloured, entire, and free from dust Neumann says, that after long keeping they fall into a grey brown powder, and in this state are unfit for use, their intrinsic qualities perishing with their external form. Experience, however, contradicts this idea.
Baglivi supposed that cantharides were introduced into medicine by the Arabian physicians, though they were evidently known to Hippocrates; but the animal appears to have been different. From the description of Dioscorides, the ancient physicians apparently employed the mylabrum cicliorci. The Chinese, at this moment, use the same insect for the purpose of blistering; and the mylabrum is very common in the east, where Dioscorides lived. The attention paid to the cantharis has occasioned the other kinds to be neglected. Many of the species arc perhaps equally active, and others may, from a less degree of acrimony.
be adapted for internal use. Of the other genera, which may be equally useful, the meloe, the mylabrum, the scarabaeus, tenebrio, cicindela, and coccinella, may be suggested as subjects of trial. Many of the caterpillars contain on their bodies an acrid dust, which, dispersed in the air, irritates the skin and the eyes.
Cantharides appear in troops or swarms, and are discovered by their fetid smell. They are usually shook from the tree into a cloth, and exposed in a sieve to the vapour of vinegar; or they are collected in a fine cloth, and repeatedly immersed in vinegar. Another method is, to spread cloths under the trees and boil vinegar around: they are then placed for a little time in jars before they are exposed to the air to dry. They are dried in the sun, though more frequently in an airy place, from whence the sun is excluded, or covered with paper. In turning them, the workmen wear gloves, as they would otherwise experience troublesome heats of urine, ophthalmies, and pains in the neck. Cantharides, when well dried, are so light that fifty scarcely weigh a drachm.
Every animal has its enemy, and even this acrid insect is preyed on by another. Cantharides do not lose their virtue by keeping, or by having been for a long time powdered. When kept, some insect reduces them to dust, which is, however, equally efficacious with the cantharis recently powdered, for the animal seems to devour only what we shall afterwards distinguish as the parenchyma.
The chemical history of cantharides has not been sufficiently examined; and what is known has not yet been published in any English work. We have only received tolerably accurate accounts from MM. Thou-venel and Beaupoil; but, as the last, though not perfectly satisfactory, are more so than the former, we shall chiefly rest on his experiments from the 48th volume of the Annales de Chimie; premising, however, shortly the conclusions of Thouvenel, which we have only seen in the first volume of the History and Memoirs of the Royal Society of Medicine at Paris, p. 333. These insects, it is observed by M. Thouvenel, besides the parenchyma, which forms one-half of their weight, affords, 1st, An extractive matter of a green yellow colour, resembling that of ants (see Formica); 2dly, A yellow insipid oil, resembling the spirituous tincture of these animals; 3dly, A green oily concrete matter examined with much care, not unlike wax, but of a pungent taste, and resembling the insects in smell; and affording, by analysis, the same component parts. In this. M. Thouvenel thinks the chief virtue of cantharides resides; and he seems to be convinced that the extractive matter envelopes the oily, so as to prevent the latter from being wholly soluble in vinous spirits. He was thence led to employ proof spirit; and this menstruum dissolves all the green active matter with so little of the extractive, as not to impede its virtues. This tincture M. Thouvenel has employed in his medical experiments; and, when applied externally, he found it a tonic, a resolvent, useful in rheuma-tisms, sciatica, wandering gout, and pains in the side.
M. Beaupoil has engaged in the subject at a greater extent. He has described the specific characters of the cantharides, the means employed to collect them, and the preparation they undergo previous to their introduction as objects of commerce. In the second part he has slightly glanced at their use, from the time of Hippocrates to the present. In these parts there is nothing new. The third part relates to their analysis; and the fourth to the effects of the cantharides entire, or their component parts, on himself and different animals.