The stalked eyes of Bathothauma (Mollusca, Cephalopoda)

In the larvae of some cranchiid squids the eyes are carried sideways on long stalks and also possess a presumed luminous organ. The structure of this organ is described but the only sign of light producing tissues is some possible luminescent bacteria. The stalked eye may be connected with plankton feeding at great depths, perhaps improving distance judgement. The older animals of these species carry a different form of luminous organ.