406 ALLIONIACEAE 



2. ALLIONIA Loefl. 

 Perennial glabrous or glandular herbs, with forking stems. Leaves opposite : bladea 

 fleshy, drying very brittle. Flowers 1-5 in an involucre, white, pink or scarlet. Involu- 

 cre accrescent, usually conspicuously nerved, with 5 lobes. Calyx often oblique, campanu- 

 late or infundibuliforra : tube constricted above the ovary : limb erect or spreading, 

 plicate, deciduous. Stamens 2-5, unequal in length : filaments filiform, very slender, 

 rolled in, united into a cup at the base. Style filiform. Fruit club-shaped to spindle- 

 shaped or obovoid, ribbed or terete, glabrous or pubescent. Seed shaped like the pericarp 

 to which its testa adheres. Endosperm mealy. [Oxybaphus UHer.] Umbrella- wort. 



Fruit glabrous : involucres 2-3-flowered. 1. A. Texeima. 



Fruit pubescent : involucres 3-5-flo\vered. 



Leaf-blades linear, oblong, lanceolate or ovate, sessile or only the lower ones with 

 short petiole-like bases. 

 Involucres on solitary axillary peduncles. 2. A.decumbens. 



Involucres in terminal cymes. 



Stems glabrous, at least below, not hirsute, but often puberulent above. 

 Bracts of the inflorescence numerous, often consiiicuously so: upper 



leaves much reduced and resembling the bracts. 3. A. bracteosa. 



Bracts of the infloresceuce not numerous: upper leaves not couspic- 

 uotisly reduced. 

 Leaves with narrowly linear blades less than 5 mm. broad. 4. A. linearis. 



Leaves withobovate to ovate, oblong or linear-lanceolate blades mostly 

 over 5 mm. bread. 

 Calyx pink : leaf-blades thick, blunt. 5. A. lanccolata. 



Calyx white : leaf-blades thin, acute or acuminate. 6. A. albida. 



Stems more or less hirsute as well as viscid. 7. A. pilosa. 



Leaf-blades cordate to broadly ovate-lanceolate, or rarely broadly lanceolate, 

 distinctly petioled. 

 Leaves with ovale or ovate-lanceolate blades rounded or cuneate at the base. 



Stems usually copiously hirsute. 8. A. comata. 



Stems glabrous or sometimes merely puberulent above. 



Involucres less than 1 cm. broad at maturity : leaf-blades mostly cune- 

 ate at the base. 9. A. oblongifolia. 

 Involucres over 1 cm. broad at maturity : leaf-blades mostly rounded 



at the base. ' 10. .4. floribunda. 



Leaves, at least those on the lower part of the stem, with cordate blades. 11. A. riyctaffinea. 



1. AUionia Tex^nsis (Coulter) Small. Stems rather slender, glabrous, more or less 

 branched, several dm. tall : leaf-blades ovate, 2-7 cm. long, obtuse or rounded at the apex, 

 undulate, rounded or subcordate at the base ; petioles ^~\ as long as the blades : involucres 

 crisped, about 8 mm. broad, 2-3-flowered ; lobes broadly ovate, longer than the tube, 

 acute, ciliate : calyx 2-3 mm. broad, pubescent : fruit tuberculate along the ribs, glabrous. 

 [.4. corymbosa var. Texeiisis Coulter. ] 



In and near the valley of the Rio Grande, Texas. Summer and fall. 



2. AUionia decumbens (Nutt. ) Rydb. Foliage sparingly pubescent, at least when 

 young. Stems decumbent or ascending, 2-8 dm. tall, simple and tufted, or sometimes 

 branched above, the sides pul)escent, or glabrous in age : leaf-blades oblong to linear-lance- 

 olate, or rarely oblong-lanceolate, 2-11 cm. long, thick, sometimes slightly acuminate, but 

 rather blunt, ciliate, narrowly cuneate at the base, essentially sessile : involucres terminat- 

 ing solitary axillary peduncles, 1.5-2 cm. wide ; lobes acute or acutish or rarely rounded : 

 calyx sparingly pubescent, about 3 mm. broad : fruit narrowly obovoid, 5-6 mm. long, with 

 prominent ribs and tubercled faces. 



In dry or sandy soil, Missouri to Mississippi and New Mexico. Spring and summer. 



3. AUionia bracteosa Rydb. Foliage, at least that of the upper parts and the in- 

 florescence, viscid-puberuleut. Stems erect or ascending, 4-13 dm. tall, with several or 

 many a.scending or spreading branches above : leaf-blades oblong to linear-lanceolate or 

 linear, 3-9 cm. long, blunt or acutish, thick, mostly ciliate, each narrowed to the essen- 

 tially sessile ba.se : involucres often numerous, disposed in terminal cymes, 10-14 mm. 

 wide ; lobes ovate, obtuse : calyx white or pale, about 10 mm. broad : fruit oblong- 

 obovoid, 5-5.5 mm. long, prominently 8-ribbed, apiculate, con.stricted near the base. 



In dry and rocky soil, South Dakota to Missouri and Alabama. Summer and fall. 



4. AUionia linearis Pursh. Foliage glabrous, or glandular-pubescent above. Stems 

 slender, 3-15 dm. tall, terete, or 4-angled below : leaf-blades thick, linear, 2.5-10 cm. long, 

 acute, undulate, sessile, or the lower sometimes short-petioled : involucres becoming 1.5 cm. 

 broad ; lobes broadly ovate, obtuse, about as long as the tube : calyx finely pubescent, 

 campanulate, purple ; lobes ovate : stamens and style exserted : fruit oblong-obovoid, 5 mm. 

 long, 5-ribl)ed, the faces tuberculate, pubescent. 



In dry Boil, Minnesota to Texas, Utah and Mexico. Spring and summer. 



