F1. Columella structure

The overall form of the central axial structure within a corallite
 

Character State	Definition	Illustration
trabecular & continuous	Spongy columella that continues between corallite centers
trabecular & discontinuous	Spongy and discrete columella
styliform	Solid, projecting columella to which the septa are fused by secondary stereome
lamellar	Plate-like columella oriented parallel to the long axis of a corallite or corallite series
absent	No columella