Vertical intervallar structures: Longitudinal and often radial structures inside the intervallum (septa, taeniae...).
Intervallum: Space enclosed between the walls.
structure | |_ Vertical intervallar structures | |_ Type of vertical intervallar structures {None , isn't included in the term} | |_ Repartition of vertical intervallar structures pores {None , isn't included in the term} | |_ Porosity of vertical intervallar structures {None , isn't included in the term} | |_ Pores of vertical intervallar structures {None , isn't included in the term}