Heuchera halstedii Rydb.

Heuchera halstedii Rydb. sp. no v
Flowering branches 3-4 dm. high, 2-3-leaved, sparingly brownish-villous ; petioles of the basal leaves about 1 dm. long, densely brown -villous ; blades about 7 cm. in diameter, almost orbicular in outline, cordate at the base with a very deep and narrow sinus, the basal lobes almost meeting, 7-9-lobed, with rounded lobes and ovate cuspidate teeth, sparingly hirsutulous above and hirsute on the veins beneath ; leaves of the flowering branches similar but smaller and with sharper teeth ; inflorescence narrow, glandular-puberulent and with scattered hairs ; bracts linear-lanceolate, the lower pectinate-toothed ; hypanthium puberulent, together with the ovate sepals about 4 mm. long ; petals narrowly linearoblanceolate, much exceeding the sepals ; filaments about 3 times as long as the sepals.
Type collected at the foot of basalt cliffs at Hacienda de Regla, 4 leagues west of Real del Monte, Mexico, by Dr. M. B. Halsted.