Free discoid to hemispherical masses. Zooecia lined by overlapping cystiphragms connected by diaphragms. Colonies mostly dendroid, others encrusting or massive, few frondose. Feeding zooids budded throughout endozones in almost all taxa. Body cavities of feeding zooids in exozones generally equidimensional in cross section, either circular or polygonal.
Most zooidal skeletons laminated in exozones, laminae parallel to growth surfaces.
Many with small polymorphs between maculae, with or without diaphragms.