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Baxter, ROBERT W. (U. Kansas, Lawrence.) A new cordaitean stem with paired axillary branches. Amer. Jour. Bot. 46(3) : 163‐169. Illus. 1959.—A cordaitean stem tip from the middle Pennsylvania of Kansas is described as a new species, Mesoxylon birame sp. nov. The most distinctive feature of the new species is the presence of paired branches in the axil of each leaf. The possibility that these twin branches represent axes of Cordaianthus cones is discussed.
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Robert W. Baxter (1959) studied this question.
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