Two new species of platform conodonts were obtained from beds near the Middle-Upper Devonian boundary in Indiana and New York. Palmatolepis? disparalvea n.sp., differs from all species included within Palmatolepis Ulrich and Bassler by possessing a large basal cavity of unusual shape. Polygnathus alveoliposticus, n. sp., is distinguished by its posterior basal cavity and general lack of a free blade. The thin conodont-rich limestone at the base of the New Albany Shale (Devonian-Mississippian) of southern Indiana yielded the majority of specimens. The conodont fauna of the basal New Albany falls within the Schmidtognathus hermanni-Polygnathus cristatus Zone, a problematical interval between Middle and Upper Devonian.

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