Pteridium aquilinum
Vessel-like cells have also been found in the xylem of "Equisetum" (horsetails), "Selaginella" (spike-mosses), "Pteridium aquilinum" (bracken fern), "Marsilea" and "Regnellidium" (aquatic ferns), and the enigmatic fossil group Gigantopteridales. In these cases, it is generally agreed that the vessels evolved independently. It is possible that vessels may have appeared more than once among the angiosperms as well.