New Permian plant specimens are described from Prince Edward Island, Canada. They include attached specimens of leaf and stem genera Walchia and Tylodendron, enabling reconstruction of this Early Permian conifer. Although poorly preserved, the study of these floras extends our knowledge of diversity and climate conditions in the region. By placing these findings in a broader stratigraphic and geographic framework, we can document the phytogeographic and climate trends through the Carboniferous and Permian in the Maritimes Basin. Combined data on temporal trends in climate-sensitive sediments, as well as macrofloral and microfloral diversities, generally match the independently derived paleolatitudinal estimates. These show the region migrating from the southern subtropics across the Equator and into the northern subtropics between the Early Carboniferous and Early Permian. Evaporites and pedogenic carbonates, together with low-diversity floras, match its subtropical position in the Early Carboniferous. In contrast, coals are present in the Late Carboniferous, accompanied by high-diversity macro- and microfloral remains, when the region was on or near the Equator. However, the subsequent transition to pedogenic carbonates, eolian sands, and lower diversity floras is not matched by significant poleward latitudinal motion. We ascribe these changes to a decrease in moisture availability, as transgressions of epeiric seas became less frequent and finally stopped altogether, causing an increase of continentality in Euramerica.

Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Araucariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for conservation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.

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