Author Institution: Assistant Professor of Botany and Curator of the Herbarium, The Ohio State University, Columbus, Ohio 43210 and The Frans Theodore Stone Laboratory, Put-in-Bay, Ohio 43456The aquatic Angiosperm flora of the islands at the western end of Lake Erie was intensively studied by A. J. Pieters and E. L. Moseley 60-70 years ago and 20 years ago by E. L. Core. Since then, additional species have been discovered, of which twenty-four are recorded here. Of these Phalaris canariensis, Scirpus acutus, Rorippa sylvestris, Hibiscus militaris, Ammannia coccinea, Epilobium hirsutum, Lycopus asper, L. europaeus, and Mentha gentilis appear to represent recent invaders. Other species, all of which are native, may have either become established recently or may have been overlooked by past workers