EVENING PRIMROSE FAMILY 161 



Calyx-lobes reflexed; petals showy, clawed; capsule coriaceous. 



Fertile stamens 4, the alternate ones rudimentary; petals 3-lobed. 



8. Clarkia. 

 Fertile stamens 8 ; petals entire, rhombic. 9. Phaeostoma. 



Anthers attached near the middle and versatile. 

 Stigma, divided into 4 linear lobes. 



Stamens equal in length ; capsule terete or round-angled. 



Ovules and seeds horizontal, Inserted in 2 or rarely more rows, 



prismatic-angled; petals fellow. 10. Oenothera. 



Ovules and seeds eiscending, in one row, not angled; buds droop- 

 ing; petals white or pink. 11. Anogra. 

 Stamens unequal in length, the alternate longer: capsule crested or 

 winged; plant acaulescent or low-stemmed. 

 Capsules with more or less distinct double crests on the angles; 



seed furrowed along the raphe. 12. Pachylophus. 



Capsules winged or at least sharply angled on the angles. 

 Plants acaulescent, cesmtose. 13. L.ivauxia. 



Plan ts caulescent, with wiry diffuse stems. 



14. Gaurella. 

 Stigma discoid or capitate. 



Stigma discoid ; hypauthlum-tube funnelform above. 



Hypanthlum-tube longer than the ovary ; stigma entire. 



1.5. Galpinsia. 

 Hypanthlum-tube shorter than the ovary ; stigma 4-toothed. 



16. Merioux. 

 Stigma capitate. 



Plant acaulescent; capsules 4- winged; hypanthlum-tube tubular- 



cylindric. 17. Tabaxia. 



Plant caulescent; capsules not winged; hypanthium-tube ob- 

 conic or funnelform. 

 Capsule linear, sessile, narrowed above. 



18. Sphaerostigma. 

 Capsule more or less clavate, pedicelled and obtuse. 



19. Chylismia. 

 Fruit indehiscent, nut-like. 



Hypanthium-tube filiform; filaments unappendaged ; ovary 1-celled. 



20. Stenosiphon. 

 Hypanthium-tube obconic; filaments with scales at the base; ovary 4-celled. 



21. Gaura 

 Flowers 2-merous; fruit indehiscent, obovoid and bristly with hooked hairs. 



22. Circaea. 



1. CHAMAENERION (Gesn.) Boehmer-Ludwig. Fike-weed. 



Style pubescent at the base; leaves lanceolate or linear-lanceolate, with the lateral veins 

 confluent in marginal loops. 

 Petals 15—20 mm. long; stem-leaves usually obtuse at the base. 1. C. exaltatufn. 



Petals 8-12 mm. (rarely 15 mm.) long; leaves all acute at the base. 



2. C. spicatum. 

 Style glabrous; lateral veins of the leaves obsolete, not looped. 



Leaves lanceolate to ovate, entire or neaily so; pod about 3 mm. thick. 



3. C. lattfoUum. 

 Leaves narrowly Unear-lanceolate, denticulate; pod about 2 mm. thick. 



4. C. subdeniaium. 



2. EPILOBIUIVI (Gesn.) L. Willow-herb, Cotton-weed. 



Petals pm-ple, pink or white. 



Perennials ; stigma entire or merely notched. 



Leaves oblong, oval, ovate, or lanceolate, usually dentate or denticulate. 



Plants with rosettes or tm-ions: leaves ovate or lanceolate, usually broadest 

 below the middle, and distinctly denticulate or dentate (except some- 

 times in nos. 8, 9, and 16) 

 Stem pubescent throughout; leaves also pubescent, at least when young. 

 Pubescence consisting of long silky hairs. 1. E. ursinum. 



Pubescence short and dense, crisp or glandular. 



Petals 7-8 mm. long. 2. E. Sandbergii. 



Petals 4-5 mm. long. 



Leaves ovate, permanently glandular, dark green. 



3. E. Palmeri. 

 Leaves lanceolate, glabrous in age, pale green. 



13. E. stramineum. 

 Stem glabrous below; leaves glabrous or nearly so. 



Flowers 7-8 mm. long; petals purple or dark pink; leaves ovate-lance- 

 olate. 

 Leaves sessile or nearly so; innovations by turions. 

 Seeds without apiculations; coma sessile. 



Plant tall, 5-10 dm. high; leaves dark green, sharply dentate. 



4. E. glandulosum. 

 Plant low, 2-4 dm. high; leaves light green, more indistinctly 



denticulate. 5. E. ovaiifolium. 



Seeds with a pale hyaline beak at the apex. 6. E. brevistylum. 



Leaves short-petioled; innovations by rosettes. 7. E. occidentale. 



