Swarming of Dinoflagellates in Delaware Bay, New Jersey

Abstract

Instances of red water occurring in Delaware Bay and due to the swarming of Amphidinium fusi-forme and other dinoflagellates are described. It is suggested that the characteristic color of the water which gives the phenomenon its name is due to the reddish fluorescence of the chlorophyll present in such great quantities. A factor tending to hold the cells together in dense masses, once they are brought together, may be the gelatinization of the outer envelope of the active cells, not heretofore noted in this connection.