Geological Survey Bulletin 204 Fossil Flora of the John Day Basin, Oregon

Family HIPPOCASTANACEÆ.

ÆSCULUS SIMULATA n. sp.

Pl. XV, figs. 1, 2.

Leaflets rather membranaceous in texture, broadly obovate-lanceolate in shape, somewhat unequal-sided, long, wedge-shaped at base, rather abruptly rounded above to an apparently accuminate apex; margin minutely and regularly serrate throughout except for a short distance just above the base; midrib very thick; secondaries numerous, about 15 pairs, alternate, close, mainly parallel, forking or breaking up into two or three branches near the margin and ending in the teeth, occasionally camptodrome, with fine branches on the outside which enter the teeth; nervilles numerous, thin, mainly percurrent, oblique to the secondaries; finer nervation producing minute irregular areolae.

This fine species is represented by several examples, two of the best being figured. As all are separate leaflets, it is impossible to deter mine their arrangement. They are short-petioled if not quite sessile. The smaller of the figured specimens has 6 cm. of its length preserved and was probably between 8 and 9 cm. long when perfect. It is 4 cm. wide. The larger specimen has above 9 cm. of its length preserved and is 6 cm. wide. The entire length was probably about 15 cm.

This species seems very close, indeed, to both Æsculus octandra and Æ. glabra, well-known living species of the eastern United States.

Locality.—White hill one-half mile east of original Van Horn's ranch locality. Collected by Knowlton and Merriam, July, 1901 (U. S. Nat. Mus., Nos. 8519, 8520).