Parnassia palustris.

Botanical name: 

Parnassia Palustris.—An infusion of the bark of this tree (Heh - "bark of this tree" - this plant is no tree, it's a teensy little herb. -Henriette) has been used in the treatment of epileptics, administered in teaspoonful doses three times daily.

The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.