Stipule: Leaflike appendage arising from canal-bract junction in a wall of inverted-V or V-shaped appearance.
Canal: Pore modified by skeletal structure thikening or by lintels streching. Canal length is greater than perforation diameter.
Bract: Plate stems from lintels which incompletely covering a single pore.
Lintel: Skeletal structure separating and bounding adjacent pores/canals.
IW: Inner wall.