(Plate LXXIII)

Coarse monocarpic herbs, 2.5-8 dm tall, either erect, monopodial and branched distally or (more often) branching from near base with 2-several lateral incurved- ascending major axes, the root bright yellow, the stems eglandular, purplish or greenish-stramineous, the whole glabrous except for a few weak spreading hairs on leaf- rachis and petiolules, but the raceme-axis and tail of bracts pilosulous; stipules lanceolate to broadly ovate-acuminate and ± cordate at base, (3) 5-11 mm long, foliaceous becoming papery, palmately several-nerved, the nerves livid, enclosing pallid intervals, these charged with many small honey-colored glands; intrapetiolular glands subulate, minute, caducous; post-petiolular glands small, immersed or subobsolete; leaves petioled, the main cauline ones 4-10.5 cm long, with angled and very narrowly margined rachis and (2) 3-5 (6) pairs of obovate to elliptic, short-acuminate to obtuse and mucronulate, sometimes emarginate, flat leaflets 1-3 cm long, all brighter green above, punctate and paler beneath, the leaves of some axillary spurs smaller, with 3-5 leaflets; peduncles 1.5-6 (9) cm long; spikes densely many-flowered, oblong-ovoid becoming cylindroid, disregarding bract-tails 1.3-1.6 cm diam, the axis becoming 3-15 (20) cm long; bracts persistent, papery-membranous, obcordate-navicular, folded around the calyx and keeled dorsally, the body 6-7.5 (8) mm long, in profile 3.5-5.5 mm wide, each side 4-nerved, the livid nerves forking (as in the calyx) and the vein-lets anastomosing distally, the wide, lustrously hyaline intervals charged with small honey-colored glands, the tail arising from the distal sinus divaricate and hooked downward, 2-5.5 mm long; calyx 2.5-3.4 mm long, glabrous, the tube 2-2.9 mm long, the livid ribs filiform, the plane hyaline intervals charged with 1 row of ± 5-7 minute glands, the orifice oblique, the deltate teeth 0.2-0.7 mm long; petals opening greenish-white with finally purple keel-tip, all eventually plum-purple, the banner- blade minutely glandular dorsally, the epistemonous petals perched 4.6-6.3 mm above hypanthium, eglandular; banner 7.3-8.2 mm long, the claw 4.2-5.5 mm, the deltate- cordate blade 3.3-4 mm long, 3-4.6 mm wide; wings 4.2-5.1 mm long, the claw minute, lateral, the blade broadly lance-oblong, 2-2.3 mm wide, its basal auricle longer than the claw; keel 5.2-5.8 mm long, the claws 0.7-1.2 mm, the broadly obliquely obovate blades 4-5.1 mm long, 2.7-3.2 mm wide; androecium 10-merous, 8.5-10.8 mm long, the longer filaments free for 1.6-2.2 mm, the connective gland-tipped, the anthers (0.45) 0.5-0.7 mm long; pod 2.8-3.2 mm long, obovate in profile, the style-base latero-terminal, the sutures subfiliform, the valves hyaline in lower 2/3, thence papery, glabrous, minutely gland-sprinkled; seed 2-2.3 mm long; 2n = 14 (Mosquin).—Collections: 6 (i).

Brushy hillsides on limestone, 1830-2160 m (6100-7200 ft), local but forming colonies, known only from n. Puebla, adjoining Veracruz, and centr. Oaxaca. — Flowering October- December. —Material: Puebla. Hacienda Noria, near Puebla, Arsene & Nicolas 5515 (GH, NY, P), Nicolas in 1909 (G), in 1910 (L). Veracruz. Orizaba, F. Mueller in 1855 (NY). Oaxaca. Etla: 7 mi n. of Telixtlahuaca, Ripley & Barneby 14,671 (ARIZ, CAS, DAO, F, GH, K, MEXU, MICH, NY, UC, US).

Dalea insignis (distinguished) Hemsl., Diag. Pl. Nov. 7. 1878. — "Mexico: in ditione Verae Crucis, Muller, 228..." — Holotypus, labelled "Vera Cruz to Orizaba," K! isotypi (collected in 1853, some not serially numbered), BR, NY, W! — Parosela insignis (Hemsl.) Rose, Contrib. U. S. Nat. Herb. 10: 103. 1906.

The truly distinguished D. insignis, unique in its dilated, veiny bracts which envelop the small calyces in a laterally compressed, boat-shaped sac, is nevertheless closely related to D. obovatifolia, especially to its monocarpic, small-flowered var. uncifera, hardly different in structure of the flower. The massive spike of bracts, from which the little epistemonous petals, at first greenish white but early fading dull purple, are only shortly and fleetingly exserted, is the most obviously distinctive feature of the plant, but the enlarged foliaceous stipules, resembling the bracts in texture and venation, are equally notable. Here indeed is a clear example of the ontological relationship in Leguminosae between bract and stipules, doubtless homologous structures modifiable by a common genetic rule.

Dispersal of D. insignis is still a matter for speculation, the known collections being few and poorly documented. Modern verification of its occurrence in Veracruz is required, for at least some of Mueller’s plants labelled as though from Orizaba must have originated not on the moist Gulf slope but on the arid plateau in adjoining Puebla. It is not known for certain how many actual collections are involved in the sets distributed from Puebla by Brothers Arsene and Nicolas, possibly no more than two, both from the same locality and differently dated. I thought it prudent to ignore a specimen (G) attributed to Arsene and labelled "Dos Tebecos, Morelia," which could be part of the pirated material of this collector sent out under fallacious tickets. In reality the species is positively known only from the neighborhood of the city Puebla and from the north end of the valley of Oaxaca.