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CALAMOPHYTON IN THE MIDDLE DEVONIAN OF NEW YORK STATE
Authors:Patricia M Bonamo  Harlan P Banks
Institution:Department of Botany, Cornell University, Ithaca, N. Y.
Abstract:Specimens of Calamophyton from the Middle Devonian Ashokan Sandstone near Kingston, Ulster County, N.Y., are shown to belong to C. bicephalum Leclercq and Andrews, a Belgian species. Steel needles and a stereoscopic binocular microscope were used to follow the path of the forking leaves and branching sporangiophores of the specimens through the matrix. The terete leaves dichotomized two to three times in more than one plane. Sporangiophores dichotomized once. Each branch bore three recurved lateral branches which in turn bore two sporangia. Each branch terminated in an elongate, filiform projection. Sporangia apparently dehisced longitudinally. Their walls were composed of elongate cells. Their spherical spores ranged from 86 to 166 μ in diameter and bore a trilete mark. Ornamentation consisted of coni and spinae up to 4.5 μ long. They resembled dispersed spores of Dibolisporites gibberosus var. major Richardson. This is the second occurrence of Calamophyton bicephalum and the first account of its spores. It is the second report of the genus in North America.
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