XVI International Botanical Congess

A single cylindrical abraded cone specimen, 6.5 x 2.3 cm, has been found associated with ammonites of the Lower Cretaceous, Budden Canyon Formation, near Ono, California. The specimen was embedded in bioplastic and sectioned using the cellulose acetate peel technique. The pith is composed of thick-walled parenchyma and sclerenchyma and is bounded by a prominent ring of resin canals. The secondary xylem of the cone axis forms a continuous cylinder that contains one ring of small diameter resin canals. The cortex is composed of thick-walled parenchyma and sclerenchyma and contains numerous resin canals that dilate prior to branching. Vascular traces to the ovuliferous scale and bract diverge separately from the vascular cylinder. One cortical resin canal enters the cone scale complex on the abaxial side of the scale trace. The bract, with a terete trace and two lateral resin canals, lacks an abaxial lobe. The ovuliferous scale is almost completely sclerotic with three rows of resins canals, two of which are abaxial. A prominent interseminal ridge is present between two winged seeds on each scale. This cone shows closest similarities to Pityostrobus and represents a new species.