FOUR-O'CLOCK FAMILY 257 



4. A. ammophila Greene. Glandular-puberulent perennial; stem 3-4 dm. 

 high, decumbent, branched; leaf-blades L.5-2 cm. long, oblong-elhptic, obtuse, 

 thick; flowers greenish or yellowish white; fruit bi-turbinate, with about 5 low 

 rounded crests. ^1. arenaria Rydb. A. cheradophila A. XeLs. A. Xelsonii 

 Heimerl. Sandy places: Yellowstone Park. Submont. — Mont. Au. 



5. A. nana S. Wats. Dwarf cespitose perennial, with thick caudex; stems 

 less than 1 dm. long; leaf-blades 8-20 mm. long, oval, rough-puberulent; invo- 

 lucres of 4 or 5, ovate or lanceolate bracts, 6-10 mm. long; flowers greenish, 12- 

 14 mm. long; fruit cuneate-turbinate, with 5 hollow wings. Dry ravines and 

 vaUeys: s Utah — Ariz. — Calif. So7i. Je. 



6. A. salsa R3-db. Perennial; stem ascending, 3-4 dm. high, den.sely vLscid- 

 pubescent ; leaf-blades oval or elhptic, ver\- thick, puberulent, obtuse, or the lowest 

 rounded-oval, 3-5 cm. long, 1-3 cm. wide; bracts about 15 mm. long; flowers 

 man}-, about 2 cm. long; limb about 4 mm. wide; fruit about 1 cm. long. Sandj^ 

 beaches of salt lakes: Utah. Son. My-Jl. 



7. A. fallax Heimerl. Perennial; stem erect, almost shrubbj' below, branched, 

 straw-color or white, viscid-pubescent above; leaf -blades thick, puberulent, oval, 

 those of the upper long-lanceolate, 2-5 cm. long, 1-1.5 cm. wide; flowers many, 

 about 15 mm. long; fruit with the wings about 6 mm. wide and 8 mm. long, 

 cuneate-obpyramidal. Sand\' places: Utah. Son. Au. 



8. A. elliptica A. NeLs. Perennial, with a thick root; stems several, ascend- 

 ing, 1-3 dm. long; leaf-blades fleshy, glabrous, elliptic or oval, 1.5-3 cm. long; 

 bracts obovate, subacute, 8-15 mm. long; flowers greenish white, 15-20 mm. long; 

 fruit obscurely pubescent, turbinate, truncate or somewhat obcordate, with 5 

 wings, 7 mm. long. Clay hills: Wyo. — Colo. — Utah. Son. — Suhmont. My-Jl. 



9. A. glabra Rydb. Perennial; stem ascending, about half a meter high; 

 leaf -blades oval to oblong, thick, 1-4 cm. long, obtuse; bracts obovate, about 

 5 nrni. long, acute; flowers 12-15 mm. long, numerous; fruit cuneate-obpyramidal, 

 with the wings 4-5 mm. wide; wings very thick, of two lamina, semi-cordate at 

 the apex. Arid places: Colo. Son. Jl. 



10. A. lanceolata Rydb. Perennial; stem glabrous, decumbent, several 

 decimeters long; leaf -blades oblong-oval, rather thick, glabrous, 2-5 cm. long, 

 1-1.5 cm. wide; bracts 6-8, lanceolate, about 1 cm. long; flowers numerous, 

 about 1.5 cm. long, with a limb 4-5 mm. wide; fruit with the thin wings about 

 8 mm. wide, cuneate-obpjTamidal. Drifting sand: Ida. Son. Jl. 



11. A. Carletoni Coult. & Fisher. Perennial, with a thick root; stems 

 decumbent, glandular-puberulent, 2.5-4 dm. high; leaf-blades thick, linear-oblong 

 or oblong-ovate, 3-5 cm. long; bracts rose-colored, 6 mm. long; flowers rose-colored; 

 fruit turbinate, with 5 coarsely reticulate wings. Plains: Colo. Plain. My-Je. 



12. A. villosa S. Wats. Perennial; stems weak and slender, decumbent or 

 ascending, densely villous; leaf-blades 0..5-3 cm. long, ovate or elliptic, obtuse 

 or acute; bracts 6-8 mm. long; flowers pink, 15-20 mm. long; fruit with 3-5 

 broad wings, membranous, with a simple lamina, truncate above. Sandy places: 

 Ariz. — -s Utah — Cahf. L. Son. Ap-Au. 



2. TRIPTEROCALYX Hook. Sand Puffs. 



Branched annuals, with opposite petioled leaves. Blades entire and usuallj- 

 oblique at the base. Flowers perfect, in heads surrounded by 4-6 distinct bracts. 

 Perianth corolla-hke, salverform, with elongated tube and 5-lobed limb. Sta- 

 mens 5, regularly adnate to the perianth-tube. Fruit almost orbicular in out- 

 line, completely surrounded by 2-4, strongly reticulate, membranous wings. 

 Seeds cylindric-ellipsoid. 



Flowers 3 cm. or more long; limb about 1 cm. wide; pedvmcles longer than the leaves. 



1. T. cyclopterus. 

 Flowers 1.5-2 cm. long; limb about 5 mm. wide. 



Stem glabrous or nearly so; peduncles often nearly equalling the leaves. 



2. T. pedunculatus. 

 Stem densely pubescent; peduncles at least in flower much shorter than the leaves. 



3. T. micranthus. 



12* 



