The members of the Psaroneae comprise a family of ferns which lived during later Paleozoic times and often developed to treelike dimensions. Some believe that they were closely related to the Cyatheaceae, to which modern tropical tree-ferns belong. Most botanists, however, consider the Psaroneae a family of the order Marattiales. Members of this order still live, but, though tropical, are, for the most part, low forms with stump-like stems and enormous leaves. The Marratiales have been sometimes thought of as ancestors of the Pteridospermae, and it is possible that the Psaroneae may yet be associated with this latter group. Specimens of the fossil Psaronius have in rare instances been found in organic contact with the impressions of the frond of Pecopteris sterlzeli. This last-named species closely resembles the leaves of Pecopteris pluceneti, which according to Grand 'Eury is one of the seed-bearing forms.
Proceedings of the Iowa Academy of Science
©1914 Iowa Academy of Science, Inc.
Farr, Clifford H.
"Notes on a Fossil Tree-Fern of Iowa,"
Proceedings of the Iowa Academy of Science, 21(1), 59-65.
Available at: https://scholarworks.uni.edu/pias/vol21/iss1/11