Additional sheath: Second part of a wall composed by two zones (carcass + sheath).
Bract: Plate stems from lintels which incompletely covering a single pore.
Lintel: Skeletal structure separating and bounding adjacent pores/canals.
OW: Outer wall.
SW: Single wall.
Type of additional sheath (OW/SW) | |_ Repartition of bracts on additional sheath (OW/SW)