"Section through sea anemone. A, B, Directive septa; m.f., mesenteric filaments; g., genital organs; m.l., longitudinal muscles; s., primary septum; s'., secondary septum; s''., tertiary septum. The arrow enters between two primary septa (an intra-septal cavity), and passes out between two tertiary septa." -Thomson, 1916

Sea Anemone

"Section through sea anemone. A, B, Directive septa; m.f., mesenteric filaments; g., genital organs;…