Birch Leaf Mountain Mahogany

Cercocarpus paucidentatus (S. Wats.) Britton, Trans. N. Y
Acad. Sci. 14: 31. 1894.
Cercocarpus parvifolius paucidentatus S. Wats. Proc. Am. Acad. 17: 353. 1882. Cercocarpus Treleasei C. K. Schneid. Handb. Laubh. 1: 530. 1905.
A shrub with gray bark; branches sparsely hirsute, purpurescent ; petioles very short r 1-3 mm. long, hirsute; leaf-blades 5-10 mm. long, 2-7 mm. broad, thick, obovate, rounded or emarginate at the apex, cuneate at the base, entire or slightly 2or 3-toothed at the apex, with slightly revolute margins, dark, loosely hirsute-villous above, white-tomentose and villoushirsute beneath ; flowers solitary or two in the axils, short-pedicelled ; tube of the hypanthium whitevillous, 6 mm. long, in fruit 8 mm. long; limb together with the sepals 4 mm. broad; anthers hirsute; style in fruit 3-3.5 cm. long.
Type locality: San Miguelito, San Luis Potosi. Distribution: San Luis Potosi and Hidalgo.

Cercocarpus rotundifolius Rydberg, sp. nov
A shrub with dark-brown bark and villous young twigs; petioles 2-3 mm. long; leaf-blades broadly rounded-oval or nearly orbicular, dentate above the middle, thin, dark-green and sparingly pilose or soon glabrous above, softly villous beneath, 1-3 (rarely 4) cm. long; lateral veins 4-6 on each side; teeth broadly triangular, mucronateacute; flowers 2 or 3 together; tube of the hypanthium densely villous, about 7 mm. long; limb turbinate, together with the sepals 6-7 mm. broad, villous without; achenes about 1 cm. long; style in fruit 6-7 cm. long.
Type collected in Los Angeles County, southern California, March, 1901, Geo. B. Grant 3488 (herb. N. Y. Bot. Gard.).
Distribution: Southern California and Lower California.

Cercocarpus betuloides Nutt.; T. & G. Fl. N
Am. 1: 427. Je 1840.
Cercocarpus belulaefolius Nutt.; Hook. Ic. pi. 322. O 1840.
Cercocarpus parvifolius glaber S. Wats. Bot. Calif. 1: 175. 1876.
Cercocarpus parvifolius betuloides Sargent, Silva 4: 66. 1892.
Cercocarpus betulaefolius typicus f. glabrescens C. K. Schneid. Handb. Laubh. 1: 531. 1905. A tree 3-10 m. high, with smooth bark, separating into scales falling off in the autumn; branches glabrous or nearly so; petioles 2-4 mm. long, appressed-hairy or glabrate; leaf-blades obovate or oval, 1.5-5 cm. long, 1-2.5 cm. wide, crenate-serrate above the middle with short teeth, rounded at the apex, cuneate at the base, sparingly appressed-hairy when young, soon glabrate, dark-green above, paler beneath, comparatively thin; lateral veins 5 or 6 on each side, not very thick beneath; tube of the hypanthium 8-10 mm. long, silky-strigose ; limb turbinate, silky-strigose without, glabrous within, together with the sepals 6 mm. broad; sepals broadly triangular, obtuse; stamens rather numerous; achenes 10-12 mm. long; style in fruit 6-7 cm. long.
Type locality: Santa Barbara, California.
Distribution: Central and southern California near the coast; Lower California.