Phtheiriasis

Phtheiriasis is the name applied to the affections produced by the invasion of the three well known varieties of pediculus, namely, the head-louse, body-louse, and pubic or crab louse.

The nature and appearance of these insects are so well known that we need not describe them. The first of these infests the scalp; the second confines itself to the non-hairy portions of the surface; and the third prefers the pubic region, but may be met with wherever the hairs are short, but avoiding the scalp.