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The recent discovery of a new petrified fructification from the Lewis Creek coal ball locality in eastern Kentucky adds to our knowledge of the structure and diversity of calamitean cones The incomplete specimen measures 4 8 cm long and 6 0 mm in diameter, and is composed of alternating bract and sporangiophore whorls Approximately 24 bracts are present in each whorl. Bracts arise at right angles to the axis and are fused into a shallow disk for 2 0 mm before arching distally and becoming free Six sporangiophores arise obliquely from slightly above each bract disk; each sporangiophore bears two large pendant sporangia that are attached along their distal and tangential surfaces. Sporangial walls are a single cell layer thick and are characterized by internal cell lumen partitions The distal ends of the sporangiophores are fused to form a continuous ring of tissue that surrounds the sporangia Features of the new cone are discussed in relation to those of other calamitean cones of similar age
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Rothwell et al. (1971) studied this question.
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