ONAGRACEAE. 247 



Leaves denticulate; racemes bractless. C. pacifica. 



Leaves dentate; racemes with minute bracts. C. alpina. 



Circaea pacifica Asch. & Magn. Nearly glabrous but pilose with white 

 hairs on the upper part of the stem, 12-50 cm. high; stem usually simple, 

 from a small tuber; leaves ovate-orbicular, nearly entire or slightly denticulate, 

 3.5-6 cm. long, truncate or rarely cordate at base, acute or sometimes obtuse at 

 apex; petioles one third as long to as long as the blade; bracts of the in- 

 florescence foliaceous or setaceous or none; flowers 2.5-3 mm. long, rarely 

 pinkish in the buds; fruit mostly white-hairy. 



In moist shady woods, common. 



Circaea alpina L. Much like C. pacifica but more delicate, the leaves 

 prominently toothed; racemes bractless; flowers pinkish. 

 In springy places in the mountains. 



328. ISNARDIA. 



Annual or perennial succulent herbs with prostrate creeping or 

 floating stems; leaves opposite, fleshy, narrowed into petioles 

 shorter than the blades; flowers perfect, axillary, sessile; calyx 

 turbinate, with 4 segments, persistent; petals 4 and small, or 

 none; stamens 4; filaments short; stigma 4-lobed, often nearly 

 sessile; ovary 4-celled, very short; ovules numerous; capsule 4- 

 angled, septicidal; seeds numerous. 



Isnardia palustris L. Glabrous; stems creeping or sometimes floating, 

 15-30 cm. long; leaves all opposite, ovate or oval, 1-2 cm. long, acute, petioled; 

 flowers sessile, axillary; petals very small and reddish, or none; capsules short- 

 oblong, 4-sided, sessile, not attenuate at base. 



Borders of lakes and ponds, not rare. 



329. EPILOBIUM. Willow Herb. 



Mostly perennial herbs; leaves nearly sessile, denticulate or 

 entire, alternate or opposite; flowers axillary or terminal, solitary 

 or clustered; calyx- tube scarcely prolonged beyond the ovary, 

 4-cleft; petals 4, spreading or somewhat erect; stamens 8, the 

 alternate ones shorter; fruit a dehiscent capsule; seeds numerous, 

 each with a tuft of silky hairs at the end. 



Calyx-tube not prolonged beyond the ovary; flowers 

 large. 

 Stems 1-2 m. tall; bracts small; style pubescent at 



base. E. angustifolium. 



Stems 15-50 cm. high; bracts leaf-like; style glabrous. E. latifolium. 

 Calyx-tube prolonged beyond the ovary; flowers mostly 

 small. 

 Flowers pale yellow; stigmas 4-cleft. E. luleum. 



Flowers white or pink; stigmas 4-cleft or subentire. 

 Annuals; leaves narrow; stigmas mostly 4-cleft. 

 Stems simple or but little branched, 8-20 cm. 



high; herbage crisp-puberulent. E. minutum. 



Stems usually much branched, 30-90 cm. 



high ; herbage glabrous or glandular. E. paniculatum. 



Perennials; stigmas subentire. 



