Intervallar cell: Part of intervallum bounded by adjacent radial-longitudinal partitions and tangential synapticulae.
Intervallum: Space enclosed between the walls.
Synapticula (plur. synapticulae): Narrow horizontal rod linking two adjacent vertical intervallar structures.
Calicle: Longitudinal tubelike intervallar structure, which can be hexagonal or tetragonal in cross-section.
Syrinx (plur. syringes): Intervallar structure comprising porous radial horizontal or curved tube with hexagonal or tetragonal cross-section.
Intervallum: Space enclosed between the walls.
Intervallar cells | |_ Type of Intervallar cells {None} | |_ Section of intervallar cells {None} | |_ Porosity of intervallar cells {None} | |_ Repartition of intervallar cells pores {None}