Observations on the luminescence ofPennatula phosphorea, with a note on the luminescence ofVirgularia mirabilis

Pennatula phosphoreaLinn, is a well-known luminescent animal, which was studied by that pioneer investigator, Panceri (1871,1872a,b). He found that the animal luminesces when excited, and that the light emanates from the zooids. From the region stimulated luminous waves proceed, with measurable velocity, to the extremities of the animal. Since waves can be initiated in either direction, up or down the colony, it follows that the transmission system is non-polarized. Recent studies on other species of pennatulids have shown that luminescence is under control of a nerve net (Nicol, 1955a,b,c; Daven-port & Nicol, 1956). Harvey's book onBioluminescence(1952) gives a review of pertinent literature, plus a bibliography.