836 EPILOBIACEAE 



Fruit glabrous, the angles rounded : bractlets adnate to the 



hypanthium. 5. L. polycarpa. 



Fruit puberulent, the angles square : bractlets not adnate 



to the hypanthium. 6. L. simulata. 



gg Fruit slightly broader than long, the angles winged or mar- 

 gined. 



Sepals nearly as broad as long, almost as long as the capsule : 



seeds oval. 7. L. alata. 



Sepals broader than long, % as long as the capsule : seeds 



cylindric. 8. L. lanceolata. 



2 Fruit globular. 9. L. sphaerocarpa. 



ge and fruit copiously pilose- tomentose. 10. L. pilosa. 



b. Capsules cylindric. 11. L. glandulosa. 



B. Petals longer than the sepals. 



Fruit cylindric, terete or nearly so. 12. L. linifolia. 



Fruit narrowly obpyramidal. 13. L. linearis. 



Corolla conspicuous : flowers peduncled : capsule opening by a terminal pore. 



Foliage, sepals and fruit hirsute. 14. L. hirtella. 



Foliage, sepals and fruit glabrous, puberulent or minutely appressed-pubescent. 

 Stem-leaves with closely sessile blades : petals about twice as long as the 



sepals : pedicels longer than the capsules. 15. L. mrgata. 



Stem-leaves with short-petioled blades : petals about as long as the sepals : 



pedicels shorter than the capsules. 16. L. alternifolia. 



1. Ludwigia microcarpa Michx. Stems slender, glabrous, erect or decumbent and 

 creeping, 1-4 dm. long, 3-angled, simple or much branched, often stoloniferous, the angles 

 sometimes slightly winged : leaf-blades spatulate or obovate-spatulate, 0.5-3 cm. long, acute 

 or obtuse, short-petioled : leaves of the stolons with orbicular blades : flowers inconspicuous, 

 axillary, sessile : sepals triangular, acute : petals wanting : capsules broadly obpyramidal, 

 1.5-2 mm. long. 



In muddy places, North Carolina to Florida and Mississippi. Spring to fall. 



2. Ludwigia Simpsoiiii Chapm. Stems often branched near the base, the branches 

 glabrous, simple or again branched, often slightly decumbent, 1-3 dm. long : leaf -blades 

 broadly spatulate, 1-2.5 cm. long, finely toothed near the apex : leaves of the stolons with 

 very broadly spatulate blades : flowers inconspicuous, axillary, sessile : sepals triangular, 

 much shorter than the hypanthium : petals wanting : capsules broadly turbinate, about 2 

 mm. long, depressed. 



In ditches and low grounds, western peninsular Florida. Spring to fall. 



3. Ludwigia Curtissii Chapm. Stems glabrous, erect, 2-5 dm. tall, simple or 

 branched, especially above, nearly terete, often spongy below : leaf-blades narrowly spatu- 

 late, acute, toothed above, narrowed at the base, sessile : flowers inconspicuous, axillary, 

 sessile : sepals glabrous, about as long as the hypanthium, triangular : petals wanting : 

 capsules turbinate, about 2 mm. long, terete. 



In ponds, eastern peninsular Florida. Summer and fall. 



4. Ludwigia suffruticosa Walt- Stems glabrous or rarely puberulent, 3-10 dm. tall, 

 erect or decumbent, simple and virgate or virgately branched : leaf-blades narrowly oblong 

 to narrowly lanceolate or linear, 2-10 cm. long, acute or acuminate, sessile, those of the 

 stolons broadly oblong to obovate, short-petioled : flowers inconspicuous, crowded into a ter- 

 minal head or congested panicle : sepals broadly ovate or triangular-ovate, acute : petals 

 minute or wanting : capsules broadly obpyramidal, 4-5 mm. long, longer than the per- 

 sistent sepals. 



In wet pine lands, North Carolina to Florida. Spring to fall. 



5. Ludwigia polycarpa Short & Peter. Stems glabrous, erect or nearly so, 3-9 dm. 

 tall, more or less winged : leaf-blades narrowly lanceolate, acute at each end, 5-10 cm. long, 

 rough-margined, sessile, those of the stolons spatulate : flowers inconspicuous, sessile : bract- 

 lets adnate to the hypanthium : sepals triangular-lanceolate, acute, sometimes serrulate, 

 much shorter than the mature hypanthium : petals minute, greenish : capsules glabrous, 

 slightly 4-sided, about 5 mm. high, often twice the length of the sepals. 



In swamps, Ontario to Minnesota, Massachusetts, Tennessee and Nebraska. Summer and fall. 



6. Ludwigia simulata Small. Stems puberulent, freely branching, 49 dm. tall, 

 nearly terete : leaf -blades narrowly elliptic to almost linear, 1.5-5.5 cm. long, acute at both 

 ends, entire, sessile, those of the stolons obovate to suborbicular : bractlets not adnate to 

 the hypanthium : sepals triangular or ovate-triangular, about as long as the mature hypan- 

 thium : petals minute : capsules puberulent, obpyramidal, manifestly 4-sided, about 4 mm. 

 long. 



In swamps, eastern North Carolina. Spring to fall. 



7. Ludwigia alata Ell. Stems glabrous, 3-9 dm. tall, narrowly winged, often stolon- 

 iferous : leaf-blades linear-oblanceolate to linear-lanceolate, or sometimes nearly linear, 2.5- 

 10 cm. long, those of the stolons suborbicular or spatulate : flowers inconspicuous : sepals 



