Gray, Jane&Boucot, ArthurJ. 197901 15: The Devonian land plant Protosalvinia. Lethaia. Vol. 12, pp. 57–63. Oslo. ISSN 0024–1164.
Protosalvinia (=Foerstia) shows a number of morphological features which suggest that it was a land plant, possibly an emergent aquatic. Certain kinds of biochemical data, as presently interpreted, also support the morphological evidence. The weight of evidence supports neither a fucoid nor even an algal attribution for this enigmatic plant. Protosalvinia should be treated as the representative of a separate group of land plants, as previously advocated. Tracheid-like tubes with internal spiral thickenings appear on the basis of direct comparison to be morphologically identical to those of nematophytalean origin. They may have functioned in a capacity similar to the tracheids of vascular plants. The Nematophytales are non-marine plants of uncertain taxonomic position.