The powder of the flower-heads used as insect powder.

Santonica-Santonica. - The unexpanded flower-heads of an undetermined species of Artemisia. Imported from Russia.

Characters.-Flower-heads rather more than a line in length and nearly half a line in breadth, fusiform, blunt at each end, pale greenish-brown, smooth; resembling seeds in appearance, but consisting of imbricated involucral scales with a green midrib, enclosing four or five tubular flowers; odour, strong; taste, bitter, camphoraceous. Flower-heads not round or hairy.

Composition.-Santonica contains santonin, and a compound volatile oil, allied to camphor in its action.

Dose.-10 to 60 gr.

From Santonica is made Santoninum. Santonin. C15H18O3 A neutral principle ob-tained from Santonica. Source.-Made by (1) boiling Santonica with Lime, and straining ; (2) acidulating the hot concentrated fluid portion with Hydrochloric Acid, to precipitate the santonin; (3) washing this with Ammonia and water, and drying; and (4) dissolving it in spirit, purifying with charcoal, and crystallising out.

Characters.-Brilliant, white, four-sided flat prisms, he-coming yellow by exposure to light; odourless, tasteless or feebly bitter; scarcely soluble in cold water.

Lose.-1 to 4 gr. for a child; 2 to 6 gr. for an adult.

Action And Uses. 1. Immediate Local Action And Uses

Santonin acts as a poison to the Ascaris lumbricoides, or round worm, which infests the intestine; decidealy less so to the oxyuris vermicularis, or thread-worm. It is used as our most valuable anthelmintic against the former parasite, either combined with a purgative vermifuge, such as Pulvis Scam-monii Compositus, or followed in a few hours by a laxative, such as castor-oil.

2. Action In The Blood, And 8pecific Action

Santonin is absorbed into the blood as sodium santonate ; enters the tissues; and produces peculiar disturbances of vision and the cerebral faculties. Objects appear first as blue, and then as yellow (chromatopsia), and finally colour vision is almost lost. Consciousness is disturbed, with a kind of intoxication, tremors, debility, and convulsions after large doses. Respiration is enfeebled, and the pulse reduced in frequency. These effects must be carefully avoided in ordering santonin as an anthelmintic.

3. Remote Local Action

Santonin is excreted by the kidneys as an obscure product of its oxydation in the system, which colours the (acid) urine greenish-yellow, alkaline urine red-or purple, and causes some diuresis.