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Scott, R. A., E. S. Barghoorn, and U. Prakash. (U.S. Geol. Sur., Denver, Colo.) Wood of Ginkgo in the Tertiary of western North America. Amer. Jour. Bot. 49(10): 1095–1101. Illus. 1962. —Woods of Ginkgo and extinct related genera are very rare in the fossil record in contrast to the numerous ginkgoalean leaves. Ginkgo wood may be distinguished from other gymnosperms by a combination of anatomical features herein described. Ginkgo wood from beds of Miocene age at Vantage, Washington, first identified by Beck, is assigned to a new species, G. beckii. Ginkgo wood from the upper Eocene Clarno Formation, John Day Basin, Oregon, is described as G. bonesii sp. nov. Scarcity of fossil ginkgoalean woods may reflect unusual susceptibility to degradation of their cell walls in contrast to the greater chemical resistance to degradation which features many coniferous woods.

Fossil woods representing the genera Calophyllum of Guttiferae, Terminalia of Combretaceae, and Afzelia and Intsia of Leguminosae have been identified from the Tertiary beds of NEFA. The wood specimens were collected from the bed of River Namsang near the headquarters of the Khonsa Forest Division at Deomali. These woods are of interest anatomically as well as from the standpoint of their palaeogeographic distribution.

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