Forms of the dinoflagellate Gymnodinium breve Davis in cultures.

Morphological features of forms of the marine dinoflagellate Gymnodinium breve that were observed in cultures are described. Most forms are illustrated with photographs. Culture conditions at the times that various forms were observed are given. The most common encystment stage is described and compared with other forms. General features of cell division and other possible reproduction stages are illustrated and discussed. Forms resulting from variations in physical factors and reproductive stages are discussed.