The magnificent Devonian Fern Archaeopteris hibernica, with a somewhat Adiantiform habit, bore special fertile pinnae; the fructification is still imperfectly understood, but the presence of stipules, observed by Kidston, has been adduced in support of Marattiaceous affinities.
Fern-like plants such as Sphenopterideae, Archaeopteris and Aneimites, with occasional arborescent Pecopterideae, are frequent; many of the genera, including Alethopteris, Neuropteris and Megalopteris, probably belonged, not to true Ferns, but to Pteridosperms; although our knowledge of internal structure is still comparatively scanty, there is evidence to prove that such plants were already present, as for example, the genus Calamopitys.
Archaeocalamites, Bothrodendron, Archaeopteris, Megalopteris, &c. Among fern-like fronds Diplotmema and Rhacopteris are characteristic. Some of the Lepidodendreae appear to approach Sigillariae in external characters.
In the extreme south-east of New South Wales, at the head of the Genoa river, are sandstones with Archaeopteris howitti, which are an extension of the Lower Devonian beds of Victoria; while farther to the east, at Eden and Twofold Bay, are Upper Devonian sandstones.
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