574 LOASACEAE 



8- A. dispersa (S. Wats.) Rydb. Stem erect; lower leaves entire, the middle 

 ones lanceolate, entire or dentate, the uppermost ovate, entire; petals 3-4 mm. 

 long, obovate, bright yellow; capsule 2-3 cm. long. M. albicaulis iniegrifolia S. 

 Wats. M, dispersa S. Wats. Sandy soil: Mont.— Colo.— CaUf.— B.C.; Mex. 

 Son. — Submord. My-Au. 



9. A. compacta (A. NeLs.) Rydb, Stem whitish, pilose; leaves numerous^ 

 2-3 cm. long, rough-hirsute; petals obovate, 3-4 mm. long; capsule hnear-clavate, 

 10-13 mm. long, 10-12-seeded. M. compacta A, Nels. Plains and foot-hills: 

 Wyo.— Colo.— Ida.— Wash. Son.—SubmonL Je-Au. 



4. MENTZELIA (Plum.) L. Stick-leaf. 



Annual or biennial, or in the tropics even perennial herbs, scabrous, with 

 barbed hairs. Leaves alternate, relatively broad, sinuate or lobed. Flowers 

 perfect, cymose. Sepals 5, persistent. Petals also 5, deciduous. Stamens num- 

 erous; filaments fihform, united at the base with each other and with the petals 

 into a ring. Hypanthium short, tapering at the base. Placentae 3, broad and 

 band-hke, bearing the ovules in 1 or 2 rows. Capsule 3-valved at the top. Seeds 

 rather few, ellipsoid, angled, striate, neither winged, nor separated by horizontal 

 lamellae. 



1. M. oligosperma Nutt, Perennial, ^^dth a fusiform root; stem straw- 

 colored, rough-hirsute; leaves ovate or ovate-lanceolate, or sometimes rhombic, 

 coarsely dentate and often somewhat lobed, 1-6 cm. long; sepals 5-8 mm. long, 

 linear-subulate; petals lQ-15 mm. long, obovate-cuneate, cuspidate, golden 

 yellow; stamens about 20; capsule about 8 mm. long, 2 mm. thick, about 3- 

 seeded. M. Nelsonii Greene, a small-flowered form. Rocky places and hill- 

 sides: lU.— La.— Tex.— N.M.— N.D.; Mex. PlainSubmont. Je-Au. 



5, EUCNIDE Zucc. 



Annual or biennial herbs. Leaves alternate, broad, toothed or lobed, long- 

 petioled, armed w^th stinging barbed hairs. Flowers soHtary or in cymes. 

 Sepals 5, persistent. Petals 5, deciduous, united at the base. Stamens numer- 

 ous; filaments united below and adnate to the petals. Styles 5, distinct above. 

 Placentae 5, parietal; ovules numerous. Capsule broadened upwards, 5-valved 

 at the top; seeds nmnerous, longitudinally striate. 



A" 1^1 ^^^^^ Parry. Stem very hispid, \nth stinging bristles, straw-colored; 

 leaf-blades suborbicular or broadly ovate, 4-5 cm. long, the lower petioled, the 

 upper sessile; sepals lanceolate, 15-20 mm. long; petals obovate, 3-4 cm. long, 

 light yellow, short-acuminate. Sandstone cliffs: s Utah— Nev. L, Son. My. 



6. PETALONYX A. Gray. 



Erect perennial herbs, shrubby at the base, or low shrubs, scabrous wnth 

 short barbed hairs. Leaves alternate, enthe or toothed. Flowers small, in 

 terminal heads or short spikes. Hypanthiiun small, cylindric. Sepals 5, hnear, 

 deciduous. Petals 5, yellowish, long-clawed, spatulate. Stamens 5; filaments 

 free faliform. Ovary 1-celled. Style simple. Stigma entire. Ovule soUtary, 

 pendulous. Capsule oblong, bursting irregularly. Seed smooth. 



Leaves of the branches reduced, less than 1 cm. long. 1. P. ThurbcTi, 



Jjeaves of the branches not reduced, about 2 cm. long. 2. P. ParryL 



^* f'ij'^^^^^^l^ ^' ^^^y- Perennial, more or less shrubby at the base; 

 stems d-6 dm. high, finely scabrous-pubescent; leaves 6-20 mm. long, ovate or 

 triangular-ovate, thick, finely scabrous, sessile, entire or few-toothed; spikes 

 short, 1-4 cm. long; bracts 2, small, linear; sepals linear, 1 mm. long; petals white, 

 4-0 mm. long, slender-clawed; blades ovate; fruit o\^ate, 2.5 mm. long. Dry 

 sandy soil: Ariz.— s Utah— s Calif.; Mex. L. Son, My-Jl. 



2. P. Parryi A. Gray. A low shrub; bark of the stems gray and fissured, 

 that of the twigs straw-colored and scabrous-puberulent; leaves subsessile, 

 ovate or rhombic, or the lower spatulate, crenate, 1-3 cm. long, very scabrous; 



