131.  Dalea melantha Schauer

(Plates CXVI, CXVII)

Slender erect shrubs 0.6-2 (at anthesis commonly 1-1.5) m tall, the old wood furrowed and striped, the flexuous young branchlets usually livid or castaneous, smooth or only remotely and inconspicuously tuberculate, usually glabrous to the inflorescence but in a rare var. the foliage gray-silky with subappressed hairs up to 0.2-0.3 mm long, the leaflets of thick texture, usually becoming livid or black when dried, smooth above, punctate beneath; leaf-spurs 0.6-1.2 (1.4) mm long; stipules narrowly triangular or subulate, livid or brownish, 0.6-2 (2.5) mm long; intrapetiolular glands small or confluent into 1, sometimes 0; post-petiolular glands large, conic, black or livid; leaves short-petioled, ± dimorphic, the primary cauline ones (drought- deciduous) 1-2.5 (3) cm long, with margined, often sparsely punctate rachis and 2-6 (if pubescent 7-10) pairs of oblanceolate to obovate or obovate-cuneate, obtuse or emarginate but often gland-mucronate, flat or loosely folded leaflets 2-5 (7) mm long, the leaves of axillary short-shoots shorter, with fewer (mostly 5-7) smaller leaflets; spikes leaf-opposed and terminal to some lateral branchlets, often technically racemose, either sessile or pedunculate, the peduncles of the lowest and largest up to 2-4(5) cm long, the flowers moderately dense or loose and open, when pressed not concealing the villosulous axis, in outline ovoid becoming oblong, without petals (10) 12-16 mm diam, the villosulous axis finally (0.5) 1-5 (6) cm long; bracts early deciduous, lance- or ovate-acuminate, (2) 2.5-5 (6.5) mm long, boat-shaped below the middle, dorsally livid or livid-green and charged with a few large glands, either villosulous dorsally from base upward or glabrate medially and distally, either glabrous or pubescent within; pedicels (0) 0.1-1 mm long; calyx (4.7) 5.6-9.2 mm long, villous from base upward with fine spiral hairs up to (0.7) 1-1.4 mm long or the tube exceptionally glabrous, the teeth always plumose, the tube (2.5) 2.6-3.6 mm long, the ribs becoming thick and prominent, the firm, livid or pallid intervals charged with ± 5 prominent, dark orange or blackish blister-glands, the teeth triangular-aristiform, gland-spurred, spreading in age, the dorsal one a little longer than the rest, (2.2) 3.2-5.6 mm long, usually longer, rarely a little shorter than tube; petals pale greenish-yellow turning chocolate purple, brown, or black, usually all gland-tipped, the banner often and the keel sometimes charged with a few scattered glands, the epistemonous petals inserted low on the androecium (0.8-1.7 mm above hypanthium); banner 4.8-7.6 mm long, the subcarnosulous claw 2.4-3.8 mm long, the deltate- or ovate-cordate blade 2.6-4.4 mm long, (3) 3.2-5.5 mm wide, recessed at base into a shallow comet and the basal lobes incurved and adherent, forming lateral pockets; wings 6-7.4 mm long, the claw 1.8-2.7 mm, the oblong-oblanceolate blade 4.2-5.2 mm long, 2.2-3.2 mm wide; keel 7-9.2 mm long, the claws 2.7-4.2 mm, the broadly obovate blades 5-6.2 mm long, 3.1-4.2 mm wide; androecium 10-merous, 7-9.5 mm long, the longer filaments free for ± 2.5-2.9 mm, the connective gland-tipped, the anthers 0.6-0.8 mm long; pod (little known) 3.2-3.5 mm long, triangular in profile, the style-base latero-terminal, the prow prominulous, slender but cordlike, the valves hyaline in lower 1/3 papery, pilosulous and charged with a few livid glands distally; seed up to 2.3 mm long.

Graceful but inconspicuous, sparsely leafy shrubs with furrowed, alternately pale- and dark-striped bark, pliant livid twigs, proportionately large heads of plumose, long-toothed calyces, and pale greenish-yellow petals that quickly fade brown or black. The species as a whole is distinguished from the Thyrsiflorae by its comparatively few and large spiciform racemes, the flowers being in nearly all populations distinctly pedicellate; and more securely from all forms of the polymorphic D. lutea by the precociously deciduous bracts, thrown off before the petals expand. The species has a rather uniform and characteristic habit easily recognized in the field, but is variable in detail of leaves, pubescence, and proportions of the calyx. Four varieties, one strongly and two weakly differentiated from the typical, are recognized.