Perezia. Crystals of pipitzahoic acid.
Crystals of pipitzahoic acid, magn. 160 diam. Prepared by precipitating the alcoholic solution with water / by evaporating the alcoholic tincture of the root.
This image is from the article "On the Presence of Pipitzahoic Acid in the Perezias ..." in the American Journal of Pharmacy, 1884.