The rhizome and rootlets of Iris versicolor.

Characters. - Rhizome horizontal, consisting of joints, two to four inches (5 to 10 centimetres) long, cylindrical in the lower half, flattish near the upper extremity, and terminated by a circular scar, annulated from the leaf-sheaths, grey-brown; rootlets long, simple, crowded near the broad end; odour slight; taste acrid, nauseous.

Preparations.

Dose.

Extractum Iridis.......................................................................................

2-4 gr.

,, ,, Fluidum .........................................................................

5-10 min.

Composition. - It owes its medicinal virtues to an oleoresin. Action. - It is emetic and cathartic, and has been proved by Professor Rutherford to act as a stimulant to the liver and the intestinal glands (p. 403).

Uses. - In constipation and biliousness.