KARYOTYPES OF FIVE PLANT SPECIES WITH DISJUNCT DISTRIBUTIONS IN VIRGINIA AND THE CAROLINAS

Five species (Actaea pachypoda, Aralia nudicaulis, Cornus alternifolia, Panax quinquefolius, and Symplocarpus foetidus) display a disjunct distribution between the Mountains and Piedmont in North Carolina, South Carolina, and Virginia. The Piedmont populations are small and have apparently been isolated from the Mountain populations for several thousand years. Karyotype differences among populations were found only in A. pachypoda, and even in this species the differences were slight. The absence of population differences in four species, and the moderate differentiation found in A. pachypoda, indicate considerable cytological stability in these species.