XVI International Botanical Congess

Critical examination of samples from the coasts of Florida and Georgia revealed a diversity of forms belonging to the genus Cyclotella. Included in our samples are C. choctawhatcheeana Prasad, C. litoralis Lange & Syvertsen, C. meneghiniana Kuetzing, C. striata (Kuetzing) Grunow, C. stylorum Brightwell, and three forms which could not be placed in any described taxon. The first is distinguished by a domed central region with a ring of fultoportulae. The second resembles C. stylorum, but can be distinguished by what appears in LM to be a thickened ridge across the central region and by the presence of three-pored marginal fultoportulae. The third resembles C. meneghiniana, but differs in the arrangement of marginal fultoportulae, the orientation of the rimoportula, and in other fine structural details.