Figure 3
From: Development and epithelial organisation of muscle cells in the sea anemone Nematostella vectensis
Muscles of the adult polyp revealed by F-actin staining with phalloidin. A Cross-section of a whole mesentery with proximal parietal muscle and distal retractor muscle. B Detail of A. Parietal muscle. Note the transition of the columnar circular muscle (arrows) into the longitudinally orientated parietal muscle (arrowhead). C Detail of A. Retractor muscle (arrow). D Cross-section of a tentacle. E Detail of D. The well-formed longitudinal muscle is located basiepithelially in the epidermis (arrowhead), whereas the circular muscle is weakly developed and located in the gastrodermis (arrow). F Single longitudinal optical section of a tentacle showing the strong longitudinal muscle filaments (arrowhead) overlying those of the circular muscle (arrow). white: DAPI, orange: phalloidin.