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

Family HAMAMELIDACE&AEig;.

LIQUIDAMBAR EUROPÆUM Al. Br.

LIQUIDAMBAR EUROPÆUM Al. Br. Newberry, Later Extinct Floras, p. 100, Pl. XLVII, figs. 1—3, 1898 (1899).

As Newberry well says (op. cit. p. 101), this species is hardly to be distinguished from large leaves of Lesquereux's Liquidambar californicum, from the Auriferous gravel of California. But it appears that the large form is rare among the Auriferous gravel examples, most of them being much smaller and only three lobed. It therefore seems best to keep them apart for the present, although they are undoubtedly close. Its identity with the European form is also a matter for future settlement.

Locality.—Bridge Creek, Grant County, Oregon. Collected by Rev. Thomas Condon (U. S. Nat. Mus., Nos. 7094, 7095, 7096).

LIQUIDAMBAR EUROPÆUM PATULUM, n. var.

Pl. X, fig. 5.

Liquidambar europœum Al. Br. Lesquereux, Proc. U. S. Nat. Mus., Vol. XI, p, 14, 1888.

This specimen, the only one thus far found at this locality, was referred by Lesquereux, without comment, to L. europœum. It is a well-known fact that this is a very variable species, which more than likely covers several distinct forms, but the leaf under consideration differs markedly from any that I have seen figured in European books. It is distinctly different from the large five- to seven-lobed leaves found at Bridge Creek, nor is it the same as Lesquereux's L. californicum, from the Auriferous gravels. I have therefore ventured to give it subspecific rank under the name of L. europœum patulum. It may be described as follows: Leaf coriaceous in texture, three-lobed and much broader than long; central lobe obtusely elliptical; lateral lobes lanceolate-acuminate, nearly at right angles to the central lobe; margin finely and sharply serrate throughout.

The width of this leaf is about 14 cm. and the length only about 8 cm. The central lobe is about 4 cm. broad and the same in length, while the lateral lobes are but little more than 2.5 cm. broad.

Locality.—Van Horn's ranch, South Fork of John Day River, about 12 miles west of Mount Vernon, Grant County, Oregon. Collected by Maj. Charles E. Bendire (U. S. Nat. Mus., No. 8544).

LIQUIDAMBAR PROTENSUM ? Unger.

LIQUIDAMBAR PROTENSUM ? Unger. Lesquereux, Proc. U. S. Nat. Mus., Vol. XI, p. 13, Pl. VIII, fig. 3, 1888.

I regard this identification as extremely doubtful. The specimen lacks practically all of the margin, and other of its characters have been distorted. As Lesquereux suggests (op. cit., p. 13), this leaf has a striking resemblance to his Acer dimorphum, but the specimen is not sufficiently perfect to warrant the assertion that it represents a leaf of that species.

Locality.—Van Horn's ranch, South Fork of John Day River, about 12 miles west of Mount Vernon, Grant County, Oregon. Collected by Maj. Charles E. Bendire (U. S. Nat. Mus., No. 2504).

LIQUIDAMBAR PACHYPHYLLUM, n. sp.

Pl. IX, fig. l.

Leaf of small size, very thick in texture, five-lobed, the lobes short, ovate, or ovate-lanceolate, acute; margin serrate throughout, the teeth rather large, upward pointing; ribs arising just inside the lower mar gin of the blade, very strong, passing to the apices of the lobes; secondary branches numerous, alternate, often irregular, camptodrome, arching near the margin; nervilles very irregular, producing a coarse, heavy network.

The single broken example figured is all that was found in the collections. It was clearly live-lobed, but only the two lower and a part of one middle lobe is preserved. The total length appears to have been between 5 and 6 cm., or possibly a little more. The width between the two lower lobes is 5.5 cm.

This species had evidently a very thick, pulpy leaf, and the nervation is especially strong, particularly the ribs and nervilles.

Leaves of this genus appear to be rare in the Mascall beds, and the leaf under consideration is wholly unlike any before detected. The leaves referred to L. europœum patulum and L. protensum are thin, being like the living species in texture, whereas ours is clearly a thick leaf with a strong nervation. It is also unlike L. californicum, from the Auriferous gravels.

Locality.—Mascall beds, Van Horn's ranch, about 12 miles west of Mount Vernon, Grant County, Oregon. Collected by Knowlton and Merriam, July, 1901 (U. S. Nat. Mus., No. 8534).

LIQUIDAMBAR sp. ?

Pl. XII, fig. 4.

The collection contains one leaf that apparently belongs to Liquidambar, but it is much broken, and does not show all the characters. This example, shown in Pl. XII, fig. 4, is a large leaf, five or possibly seven lobed, the lower lobes being at right angles with the midrib, producing a novel truncate base. The width between these two lobes is nearly 14 cm. The margin of the lobes is provided with numerous fine teeth. The nervation is well marked, consisting of about five strong ribs, which radiate from the top of the petiole and presumably end in the tips of the lobes. Each is provided with numerous secondary branches, and from the larger size of some it is presumed that they supplied lateral lobes. The finer nervation is that of Liquidambar.

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., No. 8545).