LOASA FAMILY 573 



thium cylindric; placentae 3, filiform; ovules 10-40, in a single row on each pla- 

 centa. Capsule slender, linear-cylindric or linear-clavate. Seeds rather few, 

 pendulous, more or less prismatic, muricate, not striate, not separated from each 

 other by horizontal lamellae. 



Inflorescence congested; bracts broad. 3-lobed, membranous at the base. 



1. ^. congesta. 

 Inflorescence open; bracts neither 3-lobed nor membranous. 



Seeds rather strongly muricate; upper leaves narrow; sepals lanceolate-subulate, half 



as long as the petals or longer. 

 Petals 3-6 mm. long. 



Leaves pinnatifld with many lobes; petals 5-6 mm. long. 



Leaves divided to nedx the midrib, with ascending lobes; plant erect. 



2. A. gracilis. 

 Leaves divided one-half or one-third to the midrib, with divergent lobes; 



plant ascending or diffuse. 3. A. ctenophora. 



Only the middle leaves pinnatifld with few lobes, or seldom aU entire; petals 

 3^ mm. long. 4. A. albicaulis. 



Petals 2-3 mm. long; plant very slender. 



Leaves deeply pinnatifld, with narrow lobes. 5. A. Tweedyi, 



Leaves narrowly linear, entire. 6. A. tenerrima. 



Seeds minutely muricate (tubercles seen only under strong magnification) ; at least 



the upper leaves broadly ovate. 

 Petals 5 mm. long; sepals about half as long, lanceolate, acute; plant tall and 



stout. 7. A. lati folia. 



Petals 3^ mm. long; sepals linear, obtuse, only one-third as long as the petals. 

 Plant taU, 3-5 dm. liigh; capsiiles 2-3 cm. long; lower leaves lanceolate or 



linear, some of them usuaUy toothed. 8. A. dispcrsa. 



Plant low, less than 2 dm. high; capsule 12-15 mm. long; leaves all ovate, 

 entire. 9. A. compacta. 



1. A. congesta (Nutt.) Rydb. Stems white, 1-4 dm. high, somewhat 

 pilose; lower leaves hnear, entire, 4-6 cm. long; the upper ones lanceolate, some- 

 times sinuately toothed; sepals 2-3 mm. long; petals rounded-obovate ; capsule 

 8 mm. long, clavate-oblong, about 20-seeded. Hills: Ida.^-Nev. — Calif. Son, 



2. A. gracilis Rydb. Stem 3-5 dm. high; leaves 5-10 cm. long, deeply 

 pinnatifld to near the midrib; floral leaves lanceolate, sessile, pinnatifld or toothed, 

 rarely entire; sepals 4-5 mm. long; petals obovate, 6-7 mm. long, strongly striate; 

 capsule linear-cylindric, 2.5-3 cm. long. Foot-hills and plains: Colo. — Wyo. — 

 Nev, — Wash. Son. — SubmanL My-Jl. 



3. A. ctenophora Rydb. Stems 3-6 dm. long; lower leaves linear or linear- 

 lanceolate in outline, often 2 dm. long, the upper lanceolate, with a broad base, 

 all pectinately laciniate; sepals ovate-lanceolate, acute, 4—5 mm. long; petals 

 obovate, light yellow, about 8 mm. long. M. ctenophora Rydb. Sandy soil: 

 Mont. — Neb. — N.M.^^Ariz. — B.C. Plain — SubmonL Mr-Au. 



4. A. albicaulis (Dougl.) Rydb. Stem white, glabrous, erect, or decumbent 

 at the base, 1-^ dm. high; lower leaves linear-oblanceolate, usually dentate or 

 entire; middle leaves with 1-5 pairs of linear lobes, the upper linear, usually 

 entire; sepals lanceolate-subulate, 2-2.5 mm. long; petals obovate, 3-4 mm. 

 long, golden yellow, rather prominently veined; capsule linear-cylindric, 10-15 

 mm. long, 2 mm. thick. M, albicaidis Dougl. Sandy soil: Mont. — Neb. — N.M. 

 — Ariz. — B.C. Plain — SubmonL Mr-Au. 



5. A. Tweedjri Rydb. Stem very slender, erect, 1-3 dm. high, pilose when 

 young; leaves lanceolate or linear in outline, those of the inflorescence almost 

 entire; sepals 1 mm. long; petals oblanceolate, light yellow, 2-3 mm. long; cap- 

 sule linear-clavate, 15 mm. long. M. Tweedyi Rydb. Pine woods: iVIont. — 

 B.C. Plain — Sitbmont, My-Je. 



6. A. tenerrima Rydb. Stem very slender, ascending, branched, straw- 

 colored, 3-5 dm. high; leaves 2-3 cm. long, pilose; sepals linear-lanceolate, 1 mm. 

 long; petals oblanceolate, lemon-yellow, 2-3 mm. long; capsule 15 mm. long. 

 M. tenerrima Rydb. Mountain sides and dry valleys: Mont. — Utah — Ida. 

 Suhmont. — Mont, My-Au. 



7. A. latifolia Rydb. Stem 3-5 dm. high, branched; leaves sessile, ovate 

 or ovate-lanceolate, coarsely toothed or entire, 5-10 cm. long; sepals 2,5-3 mm. 

 long; petals obovate-spatulate, about 5 mm. long; capsule linear-cylindric, 2.5-3 

 cm. long. Foot-hills and mountains: Colo. SubmonL Je-Au. 



