62 LOASACE^. (MENTZELIA FAMILY.) 



sometimes unequal lobes. Capsule linear, 4-angled. Annuals, with erect brittle stems 

 and alternate leaves on short petioles. 



1. C. elegans, Doiigl. Stems from 6 inches to 6 feet high; leaves broadly ovate to 

 linear, repandly toothed; petals rhomboideal; stigma-lobes equal; capsule nearly sessile. 



2. C. rliomboidea, Dougl. Is smaller; leaves petioled; claws of the petals 

 toothed; capsule short, pediceled. 



7. EUCHARIDEUM, Fisch. & Mey. 



Distinguished from Clarkla by the filiform calyx tube prolonged above the ovary, and 

 stamens only 4. 



1. E. concinnum, Fisch. & Mey. Closely resembles Clarlla rhomhoidea in habit 

 and foliage, calyx-tube an inch long; petals 3-lobed. Common. 



8. BOISDUVALIA, Spach. 



Petals 4, obovate-cuniform, sessile, 2-lobed, purple to white. Anthers not versatile. — 

 Leaves alternate, simple, sessile; the small flowers in leafy spikes; our species villous. 



1. B. densiflora, Wat. Canescent; 6 inches to 2 ft. high; leaves lanceolate to 

 linear-lanceolate, mostly denticulate, 1 to 3 inches long; the floral leaves usually short 

 and broad; flowers in usually a close terminal leafy spike or numerous short lateral spike- 

 lets: petals 3 to 6 lines long. 



2. B. Torreyi, Wat. Eather slender, a span or two high; leaves 4 to 9 lines long; 

 the floral leaves scarcely smaller; flowers very small. 



9. Circaea, Pacilica, Asch. & Magn, In moist woods. Distinguished by its small 

 indehiscent pear-shaped fruit covered with bristles and thin ovate opposite leaves. 



Order 25. LOASACE^. 



Herbaceous plants with either stinging or jointed and rough-barbed hairs; no stipules, 

 calyx tube adnate to the 1 -celled ovary. Stamens usually very numerous. 



1. MENTZELIA, L. 



Calyx cylindrical to ovoid; the persistent limb 5-toothed. Petals 5 or 10. Stamens 

 numerous, inserted below the petals on the throat of the calyx; filaments free or in clus- 

 ters opposite the petals, filiform or the outer petaloid. Style 3-cleft, the lobes often 

 twisted. — The leaves are alternate, mostly coarsely-toothed or pinnatifid; flowers white 

 to yellow or orange. 



1. M. albicaulis, Dougl. Slender, 6 to 12 inches high or more; leaves linear-lance- 

 olate, pinnatifid with numerous narrow lobes, the upper leaves broader and often lobed 



