(Plate XCIV)

Erect suffrutescent herbs becoming shrubby and up to 2 m tall, sometimes precociously flowering when (3) 5-10 dm, commonly monopodial and virgately branching distally, pilosulous throughout or nearly so, the smooth or very sparsely verrucu- lose, green or castaneous stems at first shaggy with spreading-ascending hairs up to 0.5-1 (1.2) mm long, when old furrowed and striped, eventually glabrate, the foliage silky with ascending or subappressed, often shorter hairs, green, greenish-cinereous, or gray-silky, the leaflets punctate beneath, the inflorescence most commonly a narrow thyrse of spikes terminal to short, ascending, leafy lateral spurs (these all shorter than the primary axis and the central-terminal spike therefore surpassing all the rest), the lateral branches in var. mota elongating, the inflorescence then a broadly pyramidal panicle; leaf-spurs 0.5-1 (1.5) mm long; stipules narrowly subulate or subsetiform, 1.5-3.5 (5) mm long, livid, pubescent, each with a gland at base; intrapetiolular glands 0 or minute; post-petiolular glands prominent, conic, often concealed by vesture; leaves short-petioled or subsessile, ± dimorphic, the primary cauline ones (1) 1.5-2.5 (3.5) cm long, with 2-4 (5) pairs of oblanceolate, elliptic-oblanceolate, rarely obovate-cuneate or obovate, acute, short-acuminate, obtuse and abruptly acuminulate, rarely emarginate, loosely folded, flat, or flat and marginally involute leaflets 3-11 (14) mm long, the larger on any plant at least 6 mm long, the terminal leaflet often a trifle larger than the last pair, with them forming a palmate trefoil; peduncles all terminal to leafy branchlets, (0) 3-15 (25) mm long; spikes very dense or at least becoming so in fruit (in var. tomentosa some of the lowest flowers sometimes visibly separated from their neighbors but the rest contiguous), narrowly ovoid to conic becoming narrowly oblong-cylindroid or rarely subglobose, without petals 6.5-12 mm diam, the villosulous, pitted axis finally 1-2.5 (3) cm long; bracts deciduous but often held fast between the calyces, lanceolate or narrowly ovate-acuminate, 2-3.5 (4) mm long, firm, obscurely gland-sprinkled, dorsally pilosulous with sometimes glabrescent tips, glabrous within; calyx 2.6-4.3 mm long, varying from densely pilosulous externally to glabrous except for the teeth and orifice, the firm tube brown, pallid, or livid, 2-2.6 mm long, shallowly recessed behind banner or the whole orifice oblique, the ribs filiform, immersed or nearly so, the subulate teeth unequal, the dorsal one 0.6-1.6 (2) mm long, the rest a little broader and shorter; petals variable in color, the whitish banner early rubescent, glandless or charged near the greenish eye- spot with 1-2 very small glands, the epistemonous ones whitish, pink, lilac, or purple, glandless, perched near middle or well below middle of androecium; banner 3.1-5 mm long, the claw 1.5-2.5 mm, the deltate-cordate, often hooded blade 1.5-2.8 mm long, 1.6-3 mm wide; wings 2.1-4.3 mm long, the claw 0.4-1.1 mm, the elliptic- oblong blades 1.7-3.5 mm long, 0.8-1.7 (2) mm wide; keel 2.6-4.6 (5.1) mm long, the claws 0.7-1.2 (1.7) mm, the blades 2.1-3.9 mm long, 1.2-2.1 mm wide; androecium 10-merous, 3.5-7 mm long, the longer filaments free for 0.5-1.8 mm, the connective gland-tipped, the anthers 0.2-0.45 mm long; pod obovate in profile, 1.9-2.3 mm long, the style-base latero-terminal, the convexly arched, subfiliform prow prominulous, the valves hyaline and glabrous at base, thence thinly papery, distally pilosulous and charged with a few small glands or glandless; seed ± 1.3-1.5 mm long.

Among erect shrubby daleas of North America D. tomentosa sens. lat. is characterized by the following diagnostic syndrome: stems densely pubescent but scarcely verruculose; leaflets few (2-5 pairs) and relatively ample; spikes very dense; small calyces (less than 4.5 mm) and proportionately small petals (keel-blades 2-4 mm). The commoner forms of the species, widespread through southern Mexico and Central America, are intuitively recognized by the arrangement of the spikes, the central one being elevated above all the rest which are terminal to a succession of short axillary branchlets and together form a narrowly pyramidal or oblong thyrse (cf. Pl. CXIV). In these forms the foliage though densely pubescent is usually greenish, whereas in var. mota, a comparatively rare plant of the Pacific slope in northwestern Mexico, the leaves are permanently silvery-villosulous and the lateral axillary branchlets are both fewer and longer, raising some spikes of the second order to the level of the central one, so as to form a more open cymose panicle. All sympatric relatives of D. tomentosa southward from the Neovolcanic Belt in Mexico are, if at all similar in habit, substantially larger-flowered.