OBSERVATIONS ON LOPHODINIUM POLYLOPHUM (DINOPHYCEAE)1

Lophodinium polylophum (Daday) Lemmermann is reported from a Texas pond. Cells have distinctive longitudinal ridges, an apical carina and slit, numerous golden chloroplasts, an eyespot, and a typical dinoflagellate nucleus. The theca appears to be composed of hexagonal plates. The genus is allied to Woloszynskia Thompson, family Lophodiniaceae, but probably not to the fossil Dinogymnium.