Fern plants. Like all other vascular plants, the diploid sporophyte is the dominant phase or generation in the life cycle. The gametophytes of ferns, however, are very different from those of seed plants. They are free-living and resemble liverworts, whereas those of seed plants develop within the spore wall and are dependent on the parent sporophyte for their nutrition. A fern gametophyte typically consists of: Ferns first appear in the fossil record in the early Carboniferous period. By the Triassic, the first evidence of ferns related to several modern families appeared. The great fern radiation occurred in the late Cretaceous, when
Máedóc of Ferns Aidan, Bishop of Glendalough, referred to in the tale is unlikely to have been St. Máedóc as they had different mothers. Maedóc's mother was Eithne while Aidan's mother was Bríg, daughter of Chobtaig m. Crimthann mac Énnai m. Énnae Cennsalach of the Uí Ceinnselaig dynasty from Leinster. The grateful King Brandubh then granted him Ferns in County Wexford, where he established a monastery. The influence of Brandubh also convened a synod whereat Ferns was not merely constituted a see but its bishop Aedan was also given nominal supremacy over the other Leinster bishops as their Chief Bishop (). He was