sentences:  As water transport mechanisms and waterproof cuticles evolved, plants could survive without being continually covered by a film of water.This transition from poikilohydry to homoiohydry opened up new potential for colonisation.The early Devonian pretracheophytes "Aglaophyton" and "Horneophyton" have unreinforced water transport tubes with wall structures very similar to moss hydroids, but they grew alongside several species of tracheophytes, such as "Rhynia gwynne-vaughanii" that had xylem tracheids that were well reinforced by bands of lignin.