Bast cells. Transverse sections.
This image is from The Roots of Apocynum Androsaemifolium and Apoc. Cannabinum. in the November issue of the AJP 1881.
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.
http://www.henriettes-herb.com - Copyright 1995–2020 Henriette Kress.