EVENING PRIMROSE FAMILY. 273 



Tube of the calvx produced beyond the ovary, the limb with the free portion of the 

 calvx-tube deciduous after flowering; parts of the flower always in 4s; ovary 

 4-celled. 

 Seeds with a tuft of hairs at one end. 



Flowers large; corolla and calyx scarlet 3. Zauschneria. 



Flowers small; corolla white or purplish 4. Epilobium. 



Seeds naked. 



Flowers purple, rose-color or white, never yellow. 



Calyx-lobes erect or ascending; petals small or minute 5. Boisduvalia. 



Cah'x-lobes reflexed or the tips remaining united and turned to one side in 

 anthesis. 

 Petals distinctly clawed, often much lobed. 



Stamens 8; calyx-tube short, obconical 6. Clarkia. 



Stamens 4; calyx-tube elongated, filiform 7. Eucharidium. 



Petals sessile, not lobed except in G. bilcba; stamens 8 8. Godetia. 



Flowers yellow or (in two species) white 9. Oenothera. 



Parts of the flower in 2s; fruit bur-like 10. Circaea. 



1. JUSSIAEA L. 



Glabrous perennial herbs, ours aquatic or of muddy shores. Leaves alter- 

 nate. Flowers yellow, solitary in the axils, pediceled. Calyx-tube elongated, 

 not produced beyond the ovary, its lobes 5. Petals 5. Stamens twice as many. 

 Fruit (in ours) o-celled. Seeds very numerous. (Bernard de Jussieu, who 

 founded the natural system of classification.) 



1. J. californica Jepson. Yellow Water-weed. Stems 1 to 6 ft. long; 

 leaves oblong to obovate, % to 2 in. long, the floating ones elliptic or orbicular 

 and with longer petioles; calyx-lobes lanceolate, % in. long; petals broadly 

 obovate, 6 to 7 lines long; fruit woody, cylindric, 10 lines long, indehiscent, 

 at length reflexed and the calyx-segments deciduous from the mature fruit ; 

 fruiting pedicel y<± to % in. long; seeds large for the order, with a very thick 

 tough outer coat; cotyledons elliptic, caulicle very short. — (J. repens var. 

 californica Wats.) 



Kivers, streams and lakes, Coast Eanges east to the Sierra Nevada foothills, 

 especially common in the tide sloughs of the lower Sacramento and San 

 Joaquin rivers. 



2. LUDWIGIA L. False Loose-strife. 



Aquatic or marsh perennial herbs, with the aspect of the preceding, but the 

 leaves opposite, parts of the flower in 4s, and the petals often absent. Stamens 

 as many as the petals and alternate with them. Ovary broad at apex and 

 usually flattened, or crowned, with a conical style-base. Capsule 4-celled, 

 dehiscent by lateral slits or terminal pores. Seeds minute. (C. G. Ludwig, 

 1709-1773, Professor of Botany at Leipsic.) 



1. L. palustris Ell. Water Purslane. Glabrous, stem 6 to 12 in. long; 

 leaves obovate, acute or acuminate, narrowed at base into a rather long petiole, 

 the whole leaf 8 to 12 lines long ; petals none, or minute and reddish ; capsule 

 erect, broadly oblong," 1% lines long, more or less 4-sided or -angled, with a 

 narrow longitudinal band of tubercles on each side. 



Muddy shores: Healdsburg; Clear Lake. Aug. Fr.Sept. Capsule yellowish, 

 the persistent sepals green. 



3. ZAUSCHNERIA Presl. 



Low perennials with alternate leaves (the lowest opposite) and large scarlet 



Fuchsia-like flowers. Calyx above the ovary colored like the corolla, its tube 



funnelform with a globose base (nectar-bearing within), and appendagod 



within at the most constricted portion with several erect and deflexed scales. 



