a cutaneous disease, appearing in small watery pustules on the skin, and commonly of a mild nature, though sometimes attended with obstinate and dangerous symptoms. See Medicine, Index.

ITCH-Insect. See Acarus, Entomology, Index.

In speaking of the manner of finding these insects in the itch, Fabricius observes, that the failure of many who have sought for them has been owing to their having expected to meet with them in the larger vesicles, containing a yellowish fluid like pus; in these he informs us he never found them, but only in those pustules which were recent, and contained merely a watery fluid. We must therefore, he observes, not expect to find them in the same proportional number in patients who for many months have been afflicted with the disease, as in those in whom its appearance is recent, and where it is confined to the fingers or wrists. The cause of this difference with respect to the pustules may, he conjectures, be owing to the death of the insect after it has deposited its eggs. A small transparent vesicle being found, a very minute white point, distinct from the surrounding fluid, may be discovered, and very often even without the assistance of a glass. This is the insect, which may be easily taken out on the point of a needle or penknife, and when placed on a green cloth may be seen much more distinctly, and observed to move. But all this, we may observe, probably depends on some optical deception.