An ovulate pinaceous cone and associated needles, wood, and pollen cones were found permineralized within a small lens of chert in sediments of Middle Eocene age near Smithers, B.C. The ovulate cone, Pinus driftwoodensis sp.n., is cylindrical, about 3 cm long and 2.7 cm in diameter. Ovuliferous scales have swollen apices and an umbo lacking a spine. Pith and cortex of the axis are parenchymatous. The narrow vascular cylinder includes a ring of up to 70 resin canals. The trace to each bract and its associated ovuliferous scale arises as a single unit, circular in cross section, with an abaxial resin canal system. Two ovules with well-developed integuments but little internal tissue are borne on each ovuliferous scale. Pinaceous leaves, in two-needle fascicles, are associated with the cone. These needles contain two vascular bundles, numerous medial resin canals, stomata on both abaxial and adaxial surfaces, and a uniform hypodermis. Associated wood and small twigs have pinoid resin canals, heterogeneous rays to 14 cells high, uniseriate circular-bordered pits, and pinoid pits in the cross field, and appear similar to that described for P. similkarneenensis Miller. Pollen cones are 6 mm long and cylindrical and have dehisced prior to preservation. The ovulate cone and the two-needle fascicles are closely comparable to members of the genus Pinus, subgenus Pinus, section Pinus, subsections Sylvestres, Ponderosae, or Australes and may represent parts of the same plant.
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Ruth A. Stockey (1983) studied this question.
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