Botanical name: 

The root and stem of Brunfelsia (Franciscea) uniflora, Pohl (Nat. Ord. Solanaceae). A tropical American shrub.
Common Names: Manaca, Vegetable Mercury.

Principal Constituents.—A weak alkaloid manacine, and probably gelsemic acid.
Preparation.—Fluidextractum Franciscea, Fluidextract of Franciscea. Dose, 10 to 60 drops.

Action and Therapy.—Diuretic and probably alterative. It is employed along the Amazon for rheumatism and syphilis. It is capable of producing gastro-enteritis and death. Manaca has been proposed for rheumatism confined more to the muscles and tendons than to the articular forms, acting best when there is dull, heavy pain, soft skin and the absence of fever. It is thought to act somewhat like guaiac.

The Eclectic Materia Medica, Pharmacology and Therapeutics, 1922, was written by Harvey Wickes Felter, M.D.