—Root. A, Cross-section of root. (Photograph.)
This image is from Echinacea in Sayre's Manual of Organic Materia Medica and Pharmacognosy, 1917.

—Root. A, Cross-section of root. (Photograph.)
This image is from Echinacea in Sayre's Manual of Organic Materia Medica and Pharmacognosy, 1917.