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Variation in the Viséan coral Caninia benburbensis from north-west Ireland

Caninia benburbensis Lewis occurs in abundance in upper Visean marine limestones and shales in north-western Ireland. Study of a single assemblage reveals a range of variation which expands Lewis's concept of the species. The morphological affinity of certain variants to C. cylindrica (Scouler) strongly suggests that this Tournaisian or lower Visean species is ancestral to C. benburbensis. The morphological mode clearly distinguishes this species from all earlier caniniid populations.

On the structure of Cordaites felicis Benson from the lower Pennsylvanian of North America

New material of Cordaites felicis Benson is described from lower Pennsylvanian petrifactions collected in eastern Kentucky. Additional information about the anatomy and epidermal pattern is provided and an emended diagnosis is presented together with a discussion of other structurally preserved cordaitean leaves.

Palaeosmunda, a new genus of siphonostelic osmundaceous trunks from the Upper Permian of Queensland

Petrified osmundaceous trunks from the Upper Permian coal measures of the Bowen Basin, Queensland, are assigned to a new genus, Palaeosmunda, which possesses an ectophloic, sometimes almost simple but usually dictyoxylic, siphonostele with parenchymatous pith; the stems bear stipulate petiole bases which contain sclerotic rings that are rhomboidal in transverse section, upwards becoming laterally extended into flanges. These are the first Permian Osmundaceae definitely known to exhibit a distinct pith and leaf gaps.

Statistical analysis and presentation of trinucleid (Trilobita) fringe data

The current notation and methods of data presentation for the pits of the trinucleid fringe are reviewed and some shortcomings noted. Using a sample of Trinucleus fimbriatus Murchison investigations show that (i) operator errors in selecting half-fringes were negligible, (ii) major features of the pit distribution are not dependent on the size of specimen, (iii) statistically there are no significant differences between the left and right half-fringes, although particular individuals commonly exhibit some asymmetry.
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