4. Sanguinaria Linnaeus, Sp. Pl.  1: 505.  1753; Gen. Pl. ed. 5, 223, 1754.  
Bloodroot, puccoon, sanguinaire du Canada, sang-dragon [Latin sanguis, blood, in reference to color of sap]  
Robert W. Kiger
Herbs , perennial, scapose, from thick rhizomes; sap orange to red.  Leaves  1, or few and rosulate, sheathing-petiolate; blade 1× palmately lobed.  Inflorescences  terminal, 1(-3)-flowered; bracts absent.  Flowers:  sepals 2, distinct; petals 6-12, unequal; stamens many; pistil 2-carpellate; ovary 1-locular; style ± distinct; stigma 2-lobed.  Capsules  erect, 2-valved, dehiscing from base.  Seeds  few to many, arillate.  x  = 9.
Species 1: North America.
Sanguinaria is similar, and probably most closely related, to Eomecon Hance of eastern Asia, which is monotypic also.
SELECTED REFERENCES
Greene, E. L. 1905. Suggestions regarding Sanguinaria. Pittonia 5: 306-308. Harshberger, J. W. 1903. Juvenile and adult forms of bloodroot. Pl. World 6: 106-108. Nieuwland, J. A. 1910. Notes on the seedlings of bloodroot. Amer. Midl. Naturalist 1: 199-203.