MORPHOLOGY OF THE LUMINOUS ORGAN OF THE SQUID LOLIGO-DUVAUCELI DORBIGNY, 1839

The present paper deals with the morphology of the luminous organ of t he squid Loligo duvauceli, caught in the sea off Indonesia and Thailan d. Two luminous organs are situated on the ventral surface of the ink sac, near the anus. Each organ consists of a luminous sac divided into numerous discrete chambers containing bacteria. On the ventral side t he organ is bordered by a lens-like structure, consisting of muscle ce lls. On the remaining sides the bacterial chambers are limited by a cu p-shaped reflector layer with numerous parallel lamellae. The reflecto r separates the bacterial chamber from the ink sac. A ciliated channel connects the interior of the bacterial chamber with the mantle cavity .