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New evidence from pre-Permian strata provides an opportunity to enhance our knowledge of the earliest conifers, and together with previously known information forms the basis for evaluating both the time and mode of origin for the group. The earliest co-occurrence of eustelic stems with needle-like leaves, saccate pollen and compound ovulate strobili with bilaterally symmetrical ovules, suggests that the conifers originated at about the beginning of the Westphalian. The first extensive evidence for conifer anatomy from Pennsylvanian sediments of North America reveals remarkably modern-appearing internal features, and confirms Florin's general interpretation of the morphology of ovulate Lebachia cones. The specimens also exhibit a more specialized structure than previously suspected. Based on a basic similarity in reproductive features among conifers, cordaites and some pteridosperms, and upon the …