Part 2, 1920] FABACEAE: PSORALEAE 117 



17. THORNBERA Rydb. Jour. N. Y. Bot. Gard. 

 20:66. 1919. 



Dalea Juss. Gen. 355. 1789. Not Dalea Mill. 1754. 



Annual or perennial herbs, with glandular-dotted branches and leaves. Leaves pinnately 

 compound, with stipules and stipels, the latter often gland-like. Flowers in usually dense 

 spikes. Calyx campanula te, 10-ribbed, 5-lobed. Corolla white, rose, purple, yellow, or blue; 

 banner inserted in the bottom of the calyx, with a more or less cordate or ovate blade and a 

 long claw; other petals distinct, similar, oblong or oblanceolate to oval or obovate, subsessile, 

 somewhat oblique at the base, inserted at the mouth of the staminal tube. Stamens 9 or 10, 

 monadelphous, the upper portion of the filaments free. Ovary sessile, 2-ovuled; style filiform; 

 stigma minute. Pod membranous, enclosed in the calyx, mostly 1 -seeded, obliquely obovate, 

 somewhat compressed. 



Type species, Dalea albiflora A. Gray. 



Calyx -lobes rounded; corolla yellow. 1. T.lutea. 



Calyx -lobes triangular to subulate-filiform; corolla not yellow. 

 Corolla white. 



Leaves and stem pubescent. 



Stem and leaves long-villous. 



Leaflets 15-23; blades of the petals about 2 mm. long. 

 Leaflets 13-15; blades of the petals 3 mm. long. 

 Stem and leaves short-pubescent or puberulent; blades of the petals 3 

 mm. long. 

 Bracts longer than the calyx; leaflets broadly oblong or elliptic. 

 Bracts shorter than the calyx; leaflets linear or nearly so. 



Calyx-lobes equaling the tube; leaflets usually 7-10 mm. long. 

 Calyx-lobes shorter than the tube; leaflets 3-4 mm. long. 

 Leaves and stem glabrous. 



Leaflets oblong to oval; bracts villous-pilose throughout. 

 Leaflets linear; bracts puberulent, long-hairy only at the base. 

 Corolla (except sometimes the banner) blue or purple. 

 Perennials; bracts pubescent throughout. 

 Bracts ovate; corolla rose-purple. 

 Bracts narrowly lance-subulate; corolla blue. 

 Annuals; bracts strongly ciliate on the margins; banner white, the other 

 petals blue or rarely rose-purple. 

 Bracts broadly obovate ; plant low. 11. T. pumila. 



Bracts ovate; plant taller. 



Spikes 7-8 mm. thick. 12. T. Dalea. 



Spikes more than 1 cm. thick. 13. T. robusta. 



1 . Thornbera lutea Rydberg, sp. nov. 



Parosela rubricaidis Rose, Ms. Not P. rubrkaulis Rusby, 1910. 



A perennial herb; stem about 5 dm. high, reddish, puberulent and glandular-dotted, 

 branched; leaves 2-3 cm. long; stipules subulate, 1 mm. long; rachis red, puberulent; stipels 

 gland-like; leaflets oblong, 4-5 mm. long, glabrate above, minutely puberulent and glandular- 

 dotted beneath, rounded or slightly retuse at the apex; peduncles about 1 mm. long; spikes 

 dense, 2-3 mm. long, 8-9 mm. thick; bracts cuneate, truncate and apiculate at the apex, 

 minutely puberulent, glandular-dotted, shorter than the calyx; calyx- tube deeply cam- 

 panulate or somewhat urceolate, 4 mm. long, with 10 low black ribs, and a row of con- 

 spicuous yellow glands in the intervals, nearly glabrous; lobes rounded, glandular, 3-dentate 

 at the apex; corolla yellow; blade of the banner broadly obovate, with a pair of small basal 

 lobes, 2 mm. long, with 3 glands, one near the apex and two towards the base, the claw 2.5 mm. 

 long; blades of the other petals elliptic, slightly oblique at the base, with a gland near the apex, 

 2.5 mm. long, the claws about I mm. long; pod glabrous. 



Type collected on the west side of the Valley of Cuicatlan, Oaxaca, November 10, 1894, E W . 

 Nelson 1S96 (U. S. Nat. Herb. no. 865305). 



2. Thornbera Watsoni (Rose) Rydberg. 



Parosela Walsoni Rose, Contr. U. S. Nat. Herb. 10: 106. 1906. 



A perennial, shrubby below; stems branched, rather long-villous; leaves spreading, 1.5-3 

 cm. long; stipules filiform, 3-4 mm. long; rachis villous; stipels gland-like, conspicuous; leaf- 



