Hirudo. The Leech. Sanguisuga officinalis, the Speckled Leech; and Sanguisuga medicinalis, the Green Leech. Imported chiefly from Hamburg.

Description. Leeches have an elongated body, 2 or 3 inches long, tapering to each end, plano-convex, wrinkled transversely; of an olive-green colour on the back; made up of from 70 to 90 soft rings, with a muscular disc at both extremities, the hinder one the largest; the mouth, which is in the anterior disc, is tri-radiate, and contains three jaws, each of which is furnished with two rows of teeth; the intestinal canal is straight.

The Sanguisuga medicinalis is distinguished Joy the olive-green colour of the belly, which is unspotted; in the Sanguisuga officinalis the belly is of a yellowish-green colour, spotted with black.

Both are marked with six rusty-coloured longitudinal stripes; in the latter variety these also are spotted with black.

Therapeutics. Leeches are employed for the local abstraction of blood from those parts where cupping is not deemed advisable. The quantity of blood drawn by a leech is about one fluid drachm and a half, though by fomentation of the part perhaps half a fluid ounce may be obtained.

Bleeding from leech-bites may be stopped by pressure, by matico, by the application of collodion or of caustic; sometimes they require a suture.