Astragalus lentiginosus var. sesquimetralis

Prostrate perennial, resembling var. albifolius in habit, strigulose with sub- appressed hairs up to 0.35-0.5 mm. long, the stems stramineous, the herbage greenish, the leaflets glabrous or thinly strigulose above; stems up to "2½ ft" (7-8 dm.) long, apparently branching below the middle, simple distally; leaves 2-5 dm. long, mostly shorter than the internodes, subsessile, with 9-15 (17) oblanceolate, flat or loosely folded leaflets 6-18 mm. long, the terminal one the longest; peduncles 1.5-4 cm. long; racemes shortly but loosely 6-12-flowered, the axis ± 1-2 cm. long in fruit; calyx 7-8 mm. long, white-silky, the tube 4.8-5.5 mm. long, 2.5-2.1 mm. in diameter, the teeth 2.2-2.5 mm. long; petals purple; banner 14—14.5 mm. long, 6-6.5 mm. wide; wings ±11 mm., the blades 6-6.5 mm. long, 1.4—1.6 mm. wide; keel 9.3-9.5 mm., the blades 4.5 mm. long, 2.5 mm. wide; pod ovate or broadly lanceolate in profile, moderately inflated, 1.6-2.6 cm. long, 9-12 mm. in diameter, rounded at base, contracted into a gently incurved beak 4-8 mm. long, the valves strigulose, mottled, becoming stiffly papery, the septum ± 4 mm. wide; ovules 12(?)-20.—Collections: 1 (the typus).

Alkaline clay flats, probably ± 4000 feet, known only from the type-locality, in Esmeralda or possibly southern Mineral County, Nevada.—Not mapped.—May and June.

Astragalus lentiginosus var. sesquimetralis (Rydb.) Barneby in Leafl. West. Bot. 4: 116, Pl. II, figs. 36-38. 1945, based on Cystium sesquimetrale (l½-meter long, of the stems) Rydb. in N. Amer. Fl. 24: 414. 1929.—"Type collected at Soda Springs, Nevada, June 11, 1882, Shockley 278 (Gray Herbarium)."—Holotypus, GH! isotypi, ND, NY (fragm.), UC, US!

The name Soda Springs has been used freely and repeatedly to designate low alkaline areas in the southwestern deserts where water collects during winter or rises occasionally to the surface in salt pools or "hot pots." I have never identified the place of this name to which Shockley s label refers. I have presumed that it was not far distant from Candelaria, where Shockley was employed as a mining engineer, but repeated search in the few ostensibly suitable spots in this region has failed to rediscover the remarkable var. sesquimetralis. The plant should be very easily recognized by its long stems "creeping among grasses in moist soil," by the length of the internodes relative to the broad, short, almost sessile leaves, and by the short, headlike racemes of comparatively large flowers. The habit of growth and apparently the ecological requirements of var. sesquimentralis are closely similar to those of var. albifolius, from which it differs in the deeper calyx-tube, considerably longer petals, and a pod of stiffer texture contracted upward into an incurved and not gently decurved beak.