157.  Dalea hallii Gray

(Plate CXXXIX)

Slender perennial herbs from an enlarged woody root, strigulose up to the inflorescence with mostly appressed, and at times a few narrowly ascending hairs up to 0.3-0.6 (0.75) mm long, the 3-several wiry, decumbent but distally incurved-ascending, purplish, sometimes minutely punctate stems 1.5-3 (4) dm long, branched throughout or only in the lower 2/3 or only distally, when depauperate simple, each branch or branchlet monocephalous, the foliage pale green, the leaflets pubescent and punctate beneath, glabrous or sometimes thinly pubescent above; leaf-spurs 0.5-1.2 mm long; stipules narrowly subulate, early becoming dry and fragile, livid-tipped, 0.5-1.3 (2) mm long; leaves petioled, 1.5-4.5 cm long, pedately or palmately 3-foliolate, the margined, punctate petiole 5-12 mm, the rachis 0-1.2 mm long, the leaflets linear-elliptic or linear, abruptly acuminate or acute and livid-mucronate, flat or loosely folded, dorsally carinate by the midrib, 0.8-3 (3.5) cm long, the terminal one longest, the lowest cauline and the last rameal leaves smaller, often 1-foliolate; spikes sessile or short-pedunculate, the peduncles not over 1 cm long, relatively few- and loosely flowered, without petals ± 14-17 mm diam, the pilosulous axis becoming 1-5 cm long; bracts deciduous with or soon after the petals, subhomomorphic, ovate, broadly lance- or ovate-elliptic, acute or acuminate, 4-6.5 mm long, green and thinly herbaceous except at base, ± navicular, dorsally pilosulous and punctate; calyx (5.1) 5.5-7.8 mm long, pilose-pilosulous with spreading hairs up to 0.8-1.3 mm long, the tube 2.4-3 mm long, recessed behind banner, the ribs becoming prominent, castaneous, the flat membranous intervals charged with 1 row of 2-3 small transparent glands, the lance- aristiform, castaneous or livid teeth (3.3) 3.7-5.2 mm long, a trifle to twice longer than tube; petals yellow, seldom discolored in age, eglandular, the epistemonous ones perched near and below middle of androecium; banner 5-6.2 mm long, the claw 2.8-3.7 mm, the deltate-cordate blade obtuse or acute, 2.8-3.3 mm long, 3-3.8 mm wide; wings 4.8-6 mm long, the claw 0.8-1.4 mm, the obliquely ovate-oblong blade 3.6-5 mm long, 2.2-2.8 mm wide; keel 6.2-8 mm long, the claws 1.5-2 mm, the broadly ovate blade 5.2-6.4 mm long, 3.6-4 mm wide; androecium 10-merous, 9.5-11.5 mm long, the longer filaments free for 2.5-3 mm, the pallid anthers (0.7) 1.8-1 mm long; pod (of the section) ± 3 mm long; seed castaneous smooth ± 2.2 mm long. — Collections: 15 (i).

Gullied outcrops on calcareous or chalky prairie and rocky hillsides in oak-scrub, local and rather rare, in three small areas of e.-centr. Texas: about Dallas and Fort Worth (Dallas, Hood, and Parker cos., n. to s.-w. corner of Fannin Co.); in the hill- country near the east margins of Edwards Plateau north of Colorado River (Mills, Brown, and Comanche cos.); on and near Balcones Escarpment (Kerr, Kendall, and Hays cos.).— Flowering May to June, sometimes again August to October. —Representative: Texas. Fannin: Turner & Tharp 3133 (TEX). Dallas: Reverchon 4327 (NY). Parker: Cory 58,475 (OKLA). Hood: Tharp & Tryon 51-1096 (TEX). Mills: Tharp s. n. in 1941 (TEX, UC). Brown: Gladys Ellis 1 (OKLA). Comanche: J. Bingham 42 (OKLA). Kerr: Heller 1911 (NY, UC); Barneby 13,540 (NY). Kendall: Pennell 5481 (NY). Hays: J. C. Johnson 372 (TEX).

Dalea hallii (Elihu Hall, 1822-1882) Gray, Proc. Amer. Acad. 8: 625. 1873 ("Hallii").—"On limestone, Dallas, in Northeastern Texas, Elihu Hall, 1873, no. 132." — Holotypus, GH! isotypi, NY (2 sheets), US! — Parosela hallii (Gray) A. Heller, Contrib. Herb. Franklin & Marshall Coll. 1: 49. 1895.

A graceful plant, with wiry purplish stems, sparse trefoil foliage, and relatively loose spikes of large yellow flowers. The ribs and teeth of the calyx are usually red or chestnut- brown, contrasting with and not concealed by the thin vesture of spreading silvery hairs. As mentioned under the preceding species, D. hallii seems most nearly related to allopatric D. luisana, but is much larger-flowered. The members of sect. Cylipogon found in its range are D. aurea and D. nana, both distinguished by 5-foliolate stem-leaves.