Rubus villosus. Bark of the root.
Longitudinal section, magnified 150 diameters.
This image is from Rubus Villosus. in the December issue of the AJP 1881.
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.