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Ten different types of microproblematic structures occur on the surfaces, and in epidermal and hypodermal cells of fern pinnules preserved in the Late Pennsylvanian Grand-Croix cherts from France. These include thick-walled spheres, some with a prominent exit site, aggregations of variously sized spheres that may be surrounded by a membrane or sheath, a cylindrical structure composed of polygonal compartments, and branched hyphae/filaments with intercalary swellings protruding from a small opening in the surface (probably a stomatal pore). Some of the structures likely were produced by some fungal group, and may represent (resting) spores, microsclerotia, and conidiophores. The affinities of the others, and sometimes even their biological nature, remain difficult to determine. Nevertheless, documenting these structures is important because it provides the first indication for vascular plant leaves that were colonized by different types of organisms in a late Paleozoic ecosystem.

Sublagenicula nuda lycophyte megaspores from the upper Visean of central France frequently host a colonial green alga as an endophyte. This association was first recorded more than 100 years ago by the French paleobotanist B. Renault, who introduced the name Lageniastrum macrosporae for the alga. However, the biological significance of the discovery was not fully assessed until recently. The L. macrosporae–S. nuda association represents the oldest compelling fossil evidence for algal endophytes in land plants, and the only example to date of an alga residing in the interior of spores of vascular cryptogams. Here we present a detailed re-evaluation and photographic documentation of the surviving original specimens from the Visean of Combres/Lay and Esnost. Moreover, a newly discovered specimen from the Stephanian of central France represents the first record of this association from the Upper Carboniferous. An emended diagnosis for L. macrosporae Renault, 1896 is provided, and a lectotype and paralectotype are designated. Although L. macrosporae displays a striking suite of morphological characters found in members of the extant chlorophyte family Volvocaceae (especially the genus Volvox), the peculiar biology of the fossil necessitates establishment of a new family, for which the name Lageniastraceae is proposed. Considerations of the adaptive advantages for the alga of occupying the interior of megaspores are offered. These include the possible effectiveness of the spores in protection during periods of desiccation and against plankton-feeding animals, and use of the spores as potential vectors for dispersal from one isolated body of water to another by spore-feeding animals.

A new forewing venation pattern of the Tococladidae is proposed and the phylogenetic affinities of this family are discussed, based on Tococladus garrici nov. sp. This fossil comes from the Salagou Formation (Permian, Saxonian Group, Lodeve basin, France). The Tococladidae is assigned to the Archaeorthoptera BETHOUX and NEL, 2002 . The biostratigraphic implications of this discovery are briefly discussed, but it is still not possible to infer any definite conclusion about the age of this formation.

Morphological variability of the vegetative fronds of Dicksonites pluckenetii (SCHLOTHEIM ex STERNBERG) STERZEL is described from new material collected in the Stephanian Basin of Graissessac (Southern Massif Central France). Complete bipartite fronds sometimes still attached to their parent stem allow us to reconstruct the plant as a scrambler/climber. This interpretation is supported by the relatively small slender stems with long internodes and densely covered by short spines, which are also present along the entire length of petioles. A fertile pinna with slightly reduced pinnules bearing up to six radially symmetrical synangia is interpreted as a portion of male frond of the same species; its organization confirms the relationships of Dicksonites with the Callistophytales as was already suggested by features of the female fronds.

New material attributed to the species Iasvia reticulata ZALESSKY, 1934 and to a new species in this genus is described from the Salagou Formation (Saxonian Group, Lodeve basin). Preamble to the taxonomic section, the wing venation pattern of Orthoptera is discussed. The numerous described specimens yield decisive information about variability of wing venation within the genus, previously based on a single specimen from the Russian Permian. I. reticulata is the first species from the Lodeve basin that is already known from another site. The biostratigraphic implications are discussed.

New information is provided on gymnosperms which constitute the dominant element of the new Lower Carboniferous flora from Castelton Bay, East Lothian, Scotland. The diagnosis of the species Eristophyton waltonii is emended. It is demonstrated that this plant was arborescent with a trunk exceeding 25 cm in diameter and a monopodial branching. Another species, probably E. beinertianum, was also present at Castelton Bay. The anatomical variability of Lyginorachis waltonii is demonstrated; these rachises probably belong to Eristophyton leaves. The new data suggest close affinities between Eristophyton and Pitus. At last, the oldest representative of the progymnosperm Protopitys scotica is described from the same locality.

Resume Des informations nouvelles sont apportees sur lamorphologie des feuilles et tiges des fougeres Anachoropteris et Tubicaulis a paritur d'un materiel silicifie du Stephanien de Grand'Croix (Loire, France). Un rachis d'Anachoropteris involuta porte lateralement une tige epiphylle a protostele vitalisee semblable a celle de l'espece americaine Tubicaulis stewartii. Tubicaulis grandeuryi nov. sp. represente un autre type de tige a protostele massive, a petioles pourvus de pennes precoces et avec des ramifications (bourgeons?) axillaires reconnues pour la premiere fois dans ce genre. Le probleme de la redefinition systematique du genre Tubicaulis et de ses relations avec Anachoropteris est pose.

A large fragment of stem preserved as a compressionin argillites shows partial permineralization of the xylem and cortex. Anatomical study allows us to attribute the specimen to the genus Calamopitys , previously known only from permineralized stems. This specimen brings new evidence concerning the general morphology and habit of the Calamopityaceae which represent some of the earliest seed plants.

Resume Des silex renfermant des plantes du Viseen superieur ont ete decouverts en association avec d'autres silex a flore du Stephanien A dans le poudingue mosaique (base du Stephanien B) de Grand'Croix. Ils, confirment la provenance lointaine (region roannaise) d'elements dinantiens dans la sedimentation initiale du bassin et constituent un excellent exemple de remaniement complexe de materiel fossile vegetal.