On open seepage slopes, ditches and in bogs of e.-cen. Tex., June-Oct.; through- 

 out e. U.S., excluding Fla., n. to N.S. and Ont., w. to Kan. and Tex. 



5. Rhexia alifanus Walt. 



Erect glabrous perennial with simple or basally branched wandlike stems to 

 about 1 m. high, from an enlarged spongy rootstock; leaves ovate-lanceolate or 

 narrowly elliptic, glabrous, 3-nerved, entire, to 7.5 cm. long and 1 cm. wide, acute 

 to acuminate at apex, cuneate to the sessile base; flowers few in a paniculate cyme; 

 sepals deltoid, 1-1.5 mm. long; petals rose-color or purplish, somewhat glandular- 

 pubescent on outer surface, 2-2.5 cm. long; anthers yellow, linear-lanceolate, 

 curved, 7-8 mm. long, short-appendaged, with filaments 6-8 mm. long; mature 

 hypanthium 7-10 mm. long, glandular-setose, with a short neck; seeds lustrous, 

 brown, angled, 1-2 mm. long. 



A plant of savannahs, bogs and peaty pinelands, in s,e. Tex. (Hardin Co.), Apr.- 

 Aug.; from e. N.C., s. to Fla. and w. to Tex. 



This is one of the most distinctive of all species in this genus. It is an erect, 

 smooth plant with large, rose-color flowers. 



Fam. 95. Onagraceae Juss. Evening Primrose Family 



Herbs, sometimes woody near the base; leaves alternate or opposite, simple, 

 entire, toothed or pinnatifid; stipules minute or lacking; flowers actinomorphic or 

 slightly zygomorphic, perfect, 2-, 4- or 5- (rarely 6-) merous, borne in the axils of 

 usually reduced foliage leaves; hypanthium prolonged beyond the ovary or not; 

 sepals free; corolla white to rose-purple or yellow, the petals free; stamens as many 

 as the sepals and opposite them or twice as many; ovary 4- or 5-locular; fruit a 

 loculicidally dehiscent poricidal capsule or nutlike indehiscent structure. 



About 650 species in 19 genera, world-wide but largely extratropical; best 

 developed in subarid western North America. 



1. Calyx persistent, divided down to the ovary 1. Ludwigia. 



1. Calyx deciduous after flowering (2) 



2(1). Flowers 2-merous; fruit indehiscent, obovoid, usually with hooked hairs 

 4. Circaea. 



2. Flowers 4-merous; fruits various (3) 



3(2). Seeds with tufts of hairs (coma) at one end 2. Epilobium. 



3. Seeds without a coma 3. Oenothera 



1. Ludwigia L. Seedbox. Water-primrose 



Herbs of wet places with alternate or opposite entire or minutely toothed leaves; 

 stems spongy when in water; stipules present, minute; flowers actinomorphic, 4- or 

 5- (rarely 6-) merous, borne in the axils of upper leaves; hypanthium not prolonged 

 beyond the apex of the ovary; sepals persistent in fruit; petals yellow or absent; 

 stamens as many or twice as many as the sepals; stigma capitate or globose, undi- 

 vided; fruit a loculicidally or poricidally dehiscent capsule; seeds lacking a coma. 

 Jussiaea L. 



About 70 species, mostly of the tropics and subtropics and best represented in 

 tropical South America. 



The seeds of the various species are eaten by wildfowl, especially ducks, and the 

 base of the stem of L. palustris is said to be eaten sparingly by muskrats. 



1. Leaves opposite (2) 

 1. Leaves alternate (3) 



1175 



