Cassia Fistula.

Botanical name: 

Galen (254a) mentions a cheap cassia called "fistula," seemingly referring, not to this drug, but to a coarse cinnamon, rolled up as a tube. The fruit now known as Cassia fistula was noticed by Joannes Actuarius (4), of Constantinople, during the thirteenth century, who minutely describes it. The drug is also mentioned by writers of the school of Salernum. It was a familiar domestic remedy in England at the time of Turner (656), 1568, and as it is carthartic, it naturally appealed to heroic medicationalists. Although carried in the Pharmacopeia, it has never been much used in American medicine.

The History of the Vegetable Drugs of the U.S.P., 1911, was written by John Uri Lloyd.