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A new species of the quillwort Isoetites, I. rolandiisp. nov. Ash and Pigg, is described from the Middle Jurassic Coon Hollow Formation in the Wallowa terrane in Hells Canyon, Oregon and Idaho. The new species is based on coalified impressions and mold‐casts of an isoetaceous corm with narrow, elongate leaves, and isolated masses of leaves that have been studied using light microscopy. Plants are about 10 cm in maximum height and consist of cormose plant bases from 1.5 to 2.5 cm wide and 0.6 cm high bearing incomplete microphyllous leaves up to 8.4 cm long and 3.0 mm wide, that taper to about 2.0 mm wide distally. Associated casts of sporophyll bases and sporangia contain spherical structures about 440 μm in diameter that may represent megaspores. Based on the occurrence of complete plants, some specimens of I. rolandiiare thought to have been preserved in situ. The new Isoetitesprovides the first floristic evidence for the occurrence of an aquatic or semiaquatic paleoenvironment in the Wallowa terrane. It is also the first documented occurrence of Isoetes‐like plants in the Jurassic of western North America.

Heterangium kentuckeyensissp. nov. is described from Lower/Middle Pennsylvanian sediments of eastern Kentucky, based on permineralized stems, petioles, frond members, laminar foliage, and roots, including several organs in attachment. Stems 2.2 to 5.8 mm in diameter are known in several developmental stages. The considerable variability in stelar and cortical histology within this one species emphasizes the need to reassess variability within previously described taxa. Fronds of H. kentuckyensisare at least twice pinnate and bear primary pinnae alternately at approximately right angles. Laminar pinnules have dichotomous venation, are at least 2‐lobed, and comparable to foliage of the Sphenopteris‐type. Stomata possess 6–7 subsidiary cells with abaxial papillae. The characters used to distinguish the subgenera of Heterangiumare evaluated and found to be unreliable. Moreover, suggested phylogenetic schemes both within Heterangiumand between this taxon and other lyginopterid pteridosperms based on these features are inconsistent with stratigraphic data. Until reproductive features are known, the classification of Heterangiumspecies is best based on characters of the vegetative sporophyte, including stelar organization (particularly protoxylem architecture), cortical histology, and frond morphology.

Anatomically preserved specimens of a woody lycopsid showing the transition from the stem to the rooting region are described from the Upper Pennsylvanian Duquesne Coal of Ohio. Specimens have exarch protosteles that are apparently medullated at distal levels and exhibit abundant secondary xylem. Cortical tissues accompanying the stems have periderm, and show leaf bases or cushions. Although features of the stems are compatible with those of the arborescent Lepidodendrales, the plants have a rounded cormose rooting region, rather than the much‐branched and elongated stigmarian system usually associated with the order. Specimens of this type expand our knowledge of the diversity among Paleozoic lycopsids and document the occurrence of representatives with an Isoetes‐like base in Pennsylvanian strata.

Stems and buds of Glossopteris skaarensisPigg and buds of G. schopfiiPigg from the Permian Skaar Ridge locality in the central Transantarctic Mountains, Antarctica demonstrate the first anatomically preserved glossopterids known with stem/leaf attachment. Stems of G. skaarensisare 1–12 mm in diameter ( = 3.1 mm) with a broad pith, poorly defined primary xylem, and a zone of secondary xylem up to 6 mm thick. Pycnoxylic wood conforming to AraucarioxylonKraus is composed of tracheids with uni‐ to biseriate oval to hexagonal bordered pits on radial walls, uniseriate rays one to a few cells high, and cupressoid to taxodioid cross‐field pitting. Stems have a narrow zone of secondary phloem, aerenchymatous cortex with scattered sclereids, and sometimes a narrow periderm. Two wedge‐shaped leaf traces each bifurcate to form four strands in the base of each petiole. Small axillary branches are vascularized by double branch traces that fuse at the margin of the main axis. Buds of G. skaarensishave leaves with narrow lateral laminae and a thickened midrib containing a wide lacuna, delicate vascular strands, and a prominent hypodermis. In contrast, buds of G. schopfiihave uniformly thick leaves with prominent, circular vascular bundle sheaths. These anatomical details are used to reconstruct individual types of glossopterid plants, providing new information toward understanding the ecology and evolution of this important group of Permian seed plants.