574 LOASACEAE 



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

 ones lanceolate, entire or dentate, the ui)permost ovate, entire; petals 3-4 mm. 

 long, obovate, brigiit yellow; capsule 2-3 cm. long. M. albicaulis integrifolia S. 

 Wats. M. dispersa S. Wats. Sandy soil: IMont. — Colo. — Calif. — B.C.; Max. 

 Son. — Suhtnont. ]\Iy-Au. 



9. A. compacta (A. Nels.) Rydb. Stem whitish, pilose; leaves nmnerous, 

 2-3 cm. long, rough-hirsnte; petals obovate, 3-4 mm. long; capsule linoar-clavate, 

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

 Wyo. — Colo. — Ida. — \A'ash. Son. — Submont. 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 niuu- 

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

 into a ring. Hy])anthium short, tajjering at the bcise. Placentae 3, broad and 

 band-like, 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, with a fusiform root; stem straw- 

 coloreti, 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 10-15 mm. long, obovate-cuneate, cuspidate, golden 

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

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

 sides: 111. — La. — Tex. — N.M. — N.D.; Mcx. Plain — Submont. Je-Au. 



5. EUCNIDE Zucc. 



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

 petioled, armed with stinging barbed hairs. Flowers solitary or in cymes. 

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

 ous; filaments united below and adnate to the })eta]s. Styles 5, distinct above. 

 Placentae 5, i)arietal; ovules nmnerous. Cajisule broadened upwards, 5-valved 

 at the top; seeds nimierous, longitudinally striate. 



1. E. urens Parry. Stem very hispid, with stinging bristles, straw-colored : 

 leaf-blades suborbicultu- or broadly ovate, 4-5 cm. long, the lower jietioled, the 

 upjjer sessile; sei)als lanceolate, 15-20 mm. long; i)ctals obovate, 3-4 cm. long, 

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



6. PETALONYX A. Gray. 



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

 short barbed hairs. Leavers alternate, entire or toothed. Flowers small, in 

 terminal heads or short spikes. IIy])anthium small, cylindric. Sepals 5, linear, 

 deciduous. Petals 5, yellowish, long-clawed, sj)atulate. Stamens 5; filaments 

 free, filiform. Ovary 1-celled. Style simple. Stigma entire. Ovule solitary, 

 pendulous. Capsule oblong, bursting irregularlj*. Seed smooth. 



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



Leaves of the branches not reduced, about 2 cm. long. 2. P. Parryi. 



1. P. Thurberi A. Gray. Perennial, more or less shrubby at the base; 

 stems 3-6 dm. high, finely scabrous-pubescent; leaves 6-20 mm. long, ovate or 

 triangular-ovate, thick, finely scabrous, sessile, entire or few-toothed; si)ikcs 

 short, 1-4 cm. long; bracts 2, small, linear; se})als linear, 1 mm. long; petals white, 

 4-5 mm. long, slender-clawed; blades ovate; fruit ovate, 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; 



