Diplazium japonicum Naturalized in Florida

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In January, 1957, the junior author, in company with Mr. Paul L. Redfearn, Jr., visited the region of Lake Talquin, in Gadsden County, Florida, and collected a fern that was not recognized at the time. It was growing abundantly in a narrow ravine in hardwood forest on a steep slope north of the lake. Specimens were submitted to the senior author, who identified it as Diplazium japonicum (Thunberg) Beddome, a species not previously known naturalized in the United States, although it is fairly well known in cultivation, especially in southern California. Mrs. Fay MacFadden has it growing in her fern garden in Los Angeles. The only other Diplazium from the United States that is at all similar is D. lonchophyllum Kunze, which is known from a single locality in Louisiana.' It is a Mexican species, doubtless introduced in Louisiana, although Dr. Maxon did not reject entirely the possibility that it might be native. In the case of D. japonicum, there is no doubt but that it is introduced, even though it is growing in Florida in a distinctly rural area, isolated from any present-day farmhouses and eight to ten miles from the nearest town. It is distant about 200 yards across a forested area from a country road. Its abundance and luxuriance suggest a natural propagation regardless of how it might have come to be here in the first place. In general appearance and cutting D. lonchophyllum is not dissimilar to D. japonicum, but it differs in numerous particulars. It can be distinguished immediately by its stalked rather than sessile lower pinnae, and by the smooth rather than scaly stipes and rhachises. The only other true Diplazium known from the United States is