Botany online 1996-2004. No further update, only historical document of botanical science!
1. Tangential section with cut pith rays. Resin ducts may develop within the pith rays as can be seen with the large pith ray (cells are moving apart). Furthermore it can be recognized that the tracheids are of a limited length and sharpen towards their ends. 2. Longitudinal section with annual rings and obliquely cut pith rays. The refractions are caused by the partly air-filled cells.