10. Ludwigia sphaerocarpa Ell. Fig. 559. 



Stems thickly spongy when in water, commonly much-branched above, to 1 m. 

 tall, glabrous or finely pubescent; leaves lanceolate to linear to narrowly oblong, 

 the larger commonly 5-10 cm. long, glabrous or pubescent, tapering to the base, 

 those subtending the flowers similar in shape but much smaller; flowers subsessile, 

 separated by distant internodes; petals none; capsules subglobose, finely pubescent, 

 2.5-4 mm. long, not angled; calyx-lobes deltoid; bracteoles attached near the base 

 of the hypanthium or below it, less than 2 mm. long, very rarely more than half 

 as long as the capsule. 



Swamps and wet soil in savannahs and low pinelands, in Tex. (Angelina, Hardin 

 and Wood cos.), June-Sept.; Mass. to Fla. and Tex.; also Ind. and Mich. 



11. Ludwigia glandulosa Walt. Cylindric-fruited Ludwigia. Fig. 560. 



Glabrous or minutely strigulose erect well-branched herb to 1 m. tall; leaves 

 lanceolate or elliptical, 1.5-10 cm. long, 4-20 mm. wide, the petiole 2-10 mm. 

 long; sepals 4, 1-2 mm. long; petals absent; stamens 4; disk elevated, glabrous, 

 prominently 4-lobed, the lobes opposite the petals; capsule subcylindric, 2-8 mm. 

 long, 1.5-2 mm. thick, irregularly loculicidal, sessile; seeds in several indistinct 

 rows in each locule, about 0.6-0.7 mm. long, free. Incl. var. Torreyi Munz. 



Wet places, as along ditches and in swamps, in marsh-meadows, shallow water 

 and in mud on edge of ponds, streams and lakes, in Okla. (McCurtain, Love and 

 LeFlore cos.) and in e. Tex., June-Oct.; n. and e. to s. 111., Va. and n. Fla. 



12. Ludwigia palustris (L.) Ell. Marsh purslane. Fig. 56 L 



Glabrous herb, creeping and rooting at the nodes, the stems to 5 dm. long; leaves 

 broadly elliptical or subovate, 7-45 mm. long, 4-23 mm. wide, the petiole 3-12 

 mm. long; sepals 4, 1.4-2 mm. long; petals absent; stamens 4; disk elevated, gla- 

 brous, prominently 4-lobed, the lobes opposite the petals; capsule elongate-globose, 

 (2-) 2.5-5 mm. long, 2-3 mm. thick, fairly readily and irregularly loculicidal, 

 sessile; seeds in several indistinct rows in each locule, 0.6-0.9 mm. long, free. Incl. 

 var. americana (DC.) Fern. & Grisc. and var. nana Fern. & Grisc. 



Wet places, as along ditches and in swamps, in marsh-meadows, shallow water 

 wet gravel bars, in Okla. (LeFlore, Ottawa, Sequoyah, Craig, Haskell, Comanche, 

 Mayes and Murray cos.) and e. and s.-cen. Tex. to the Llano area and in the Davis 

 Mts., and Ariz. (Pima and Santa Cruz cos.), June-Sept.; temp. N.A. except Rocky 

 Mt. area to Col.; also in w. Euras., N. and S. Afr. and introd. elsewhere. 



13. Ludwigia repens Forst. Floating or creeping primrose-willow, water 



PRIMROSE. Fig. 562. 



Glabrous to puberulent herb, creeping and rooting at the nodes, the stems to 

 5 dm. long; leaves very narrowly elliptic to subrotund, 9-40 mm. long, 2-20 mm. 

 wide, the petiole 3-25 mm. long; sepals 4, 2.4-4.2 mm. long; petals 4-5 mm. long, 

 fugacious; stamens 4; disk elevated, glabrous, prominently 4-lobed, the lobes oppo- 

 site the petals; capsule short-cylindrical, 3.3-7.5 mm. long, 1.9-4.5 mm. thick, 

 tardily and irregularly dehiscent, the pedicel 0.3-1.5 mm. long; seeds in several 

 indistinct rows in each locule, about 0.7 mm. long, free. L. natans Ell. and var. 

 rotundata (Griseb.) Fern. & Grisc. 



Scattered in wet places as along streams and about ponds, in shallow water 

 floating on surface, wet mud on edge of water bodies, in Okla. (Alfalfa, Murray 

 and Johnston cos.) and in Tex., n. of the Rio Grande Plains but very rare in n. 

 Tex. and the Panhandle, and N.M. (Eddy and Guadalupe cos.), July-Sept.; N.C. 

 to Fla., Tex. and Okla., s. to cen. Mex. and W.I.; widely grown as an aquarium 

 plant. 



1187 



