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PINUS BUCHANANII,A NEW SPECIES BASED ON A PETRIFIED CONE FROM THE OLIGOCENE OF WASHINGTON
Authors:James C Underwood  Charles N Miller Jr
Institution:Department of Botany, University of Montana, Missoula, Montana, 59812
Abstract:A silicified seed cone of Oligocene age from the Olympic Peninsula of Washington represents a new species of Pinus. The cone was about 8 cm long and 3 cm at its widest diameter in the living condition. Its scale apices are thickened and each has a dorsal umbo. Internal cone construction confirms the assignment of the new species to Pinus and suggests affinity with the subsections Australes and Ponderosae of the section Pinus, subgenus Pinus. The cone is peculiar in having a stout bract trace that is slightly concave on its adaxial side and in having resin canals that diverge from the axial secretory system toward the bract but constrict markedly and terminate before entering the bract.
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