Cistus canadensis.

Botanical name: 

CISTUS CANADENSIS, L. Frostwort, Rock rose. Used by empirics for curing scrofula, in decoction and cataplasms. The roots throw off small white icicles.

Medical Flora, or Manual of the Medical Botany of the United States of North America, Vol. 2, 1830, was written by C. S. Rafinesque.