Fig. 235 a. - Viburnum opulus
(X 137). Group of stone cells taken from F in Fig. 235.
This image is from Cramp Bark in Sayre's Manual of Organic Materia Medica and Pharmacognosy, 1917.
A herbal distance course
Henriette's herbal is one of the oldest and largest herbal medicine sites on the net. It's been online since 1995, and is run by Henriette Kress, a herbalist in Helsinki, Finland.