Banded kokopu the dorsal and anal fins are positioned close to the tail fin, which is short and square. The caudal peduncle is short and deep, with thick fleshy flanges which join the tail fin. Adults are usually a dark, earthy brown or olive brown, with pale yellow vertical bands along the body. The belly is light coloured and unpatterned. Behind the operculum and above the pectoral fin is a silver or white mark, and sometimes a darker mark behind this. The bands either fade out top and bottom, or fork and crisscross the back of the fish. In small fish the
Operculum (gastropod) seals the shell, it can also serve as a protection against predators when the snail body is retracted. In life, the operculum is attached at the ending of the columellar muscle with an opercular disc dorsally to the upper surface of the posterior part of the foot. However, in "Buccinum" a layer of long cylindrical epithelial cells, with mostly distinct nuclei, and long divided processes enter between the muscular fibres. The operculum, a cuticular development of these cells, is composed, as may be seen in the corneous opercula of "Murex", "Purpura", "Triton", of very thin superimposed layers. The cylindrical cells