260 NYCTAGINACEAE 



late, pubescent; fruiting involucres fully 1.5 cm. broad, glabrate; lobes triangular; 

 perianth usually white; fruit obovoid, constricted near the base. A . ovata Pursh. 

 O. flonbundus Choisy. Dry- soil: S.D.— IMo.— Tex.— N.M.— Wyo. Plain. 



3. A. polyatricha Standi. Stem sparingly branched, hirsute below; 

 branches and inflorescence soft-pubescent; leaf-blades glabrous or sparingly 

 pilose, ovate, the uppermost narrowly so, obtuse or rounded at the apex; invo- 

 lucre about 1 cm. wide; lobes broadly ovate, more or less densely pubescent. 

 Canons: Colo. Jl-Au. 



4. A. hirsuta Pursh. Stem strict, 4 8 dm. high, glandular in the panicu- 

 late inflorescence; involucre glandular-pubescent, in fruit 1.5 cm. wide; lobes 

 broadly ovate; perianth purple or pink, pubescent without. A. aggregaia (Or- 

 tega) Speng., a form with axillary involucres. Sandy soil: Sask.— Minn.— 

 Neb.— N.M.— Wyo. Plain— Suhmont. Je-Au. 



1,- i,^' i"^'r^i?}°1^ (Nutt.) Rydb. Stem erect or decumbent at the base, 3-12 dm. 

 high; leaf-blades lanceolate or oblong, 2-9 cm. long, thick, nearly glabrous; 

 inflorescence cymose, glandular; fruiting involucres 1.2-2 cm. broad; lobes tri- 

 angular-ovate; perianth purplish. Dry sandy soil: Sask.— Wise— La.— Tex.— 

 Colo.— N.D. Plain— Suhmont. Jl-Au. 



6. A. Carletoni Standi. Stem about 1 m. high, simple below, soft- 

 pubescent throughout; leaves sessile or nearly so, lanceolate, very thick, acutish, 

 wavy-margined, strongly veined, 7 cm. long, puberulent on both sides; involucres 

 about 15 mm. wide, copiously soft-pubescent, the lobes rounded; fruit 5 mm. 



long with 5 prominent smooth ribs. Plains: Kans.— Colo.— Okla. Plain. 

 Je-Jl. 



7. A. glabra (S. Wats.) Kuntze. Stem &-10 dm. high, erect, branched, 

 glabrous; leaf-blades hnear, 6-12 cm. long, thick, glabrous, sessile; inflorescence 

 a large panicle; flo^vers sohtary; fruiting involucre about 1 cm. broad, glabrous; 

 lobes triangular, thm, veiny. Dry soil: s Utah— Colo.— N.M.— Ariz.; Chihua- 

 hua. Son. Au-S. 



8. A. sessilifolia Osterh. Stem stout, 5-10 dm. high, erect, branched 

 above, angled; leaves thickish, sessile, 6-8 cm. long, 4 cm. wide; involucre densely 

 hirsute, in fruit 1 cm. broad; perianth purple or pink. Valleys: Colo. Submont. 



9. A. bracteata Rydb. Stem 4-12 dm. high, erect or ascending; leaf-blades 

 oblong to Imear-lanceolate or linear, 3-9 cm. long, thick; involucres often 

 numerous, in terminal cymes, 10-14 mm. wide; lobes broadly ovate, obtuse; peri- 

 anth white or pale, about 10 mm. broad. Dry and rocky soil: Mo.— Ala.— 

 o.D. Plain. 



10. A. diffusa Heller. Stem 2-3 dm. long; leaves sessile, linear-lanceolate, 

 otten narrowly so, 5-6 cm. long, thick; fruiting involucres 7-10 mm. wide; lobes 

 triangular-ovate; perianth rose-colored to white, 6 mm. long; fruit inconspicu- 

 ously ribbed. A.glandulifera A.Neh. ^. i;iscida (East w.) Cockerell. Gravelly 



hills and sandy plains: N.D.— Kans.— N.M.— Ariz.— Wyo. Son.— Plain- 

 Mont. Je-Au. 



ui }""■* ^- ^ecumbens Xutt. Stem erect or ascending, 4-15 dm. high; leaf- 

 blades 3-10 cni long, very thick, obtuse or blunt at the apex; involucres 

 numerous, usually in terminal cymes, 1-1.5 cm. wide; lobes rounded-ovate, 

 sometunes acutish; perianth pink, about 10 mm. broad. A. decumbens was 

 origmally described from a form with axiUary involucres. A. laiiceolata Rydb. 

 represents the ordinary form. Dry sandy soil on plains and prairies: Man.— 

 Tenn.— Tex.— N.M.— Wyo. Plain— Submont. My-S. 



12. A. linearis Pursh Stem slender, 3-15 dm. high, terete or 4-angled below, 

 erect or ascending; leaf-blades thick, hnear, 2.5-10 cm. long, undulate, sessile, 

 or the lower sometimes short-petioled ; perianth finely pubescent, purple. 0. 

 angnshjohus Sweet. A. montanensis Osterh. A. Bodini (Holz.) Morong-, a 



§7™ ^''n^ f'^^^^'"^ involucres. Dry soU: Minn.— La.— Ariz.— Mont.; Max. 

 Plain — Mont. Jl-0. 



