232 FLORA OF PHILADELPHIA. 



Seeds naked. ■■ ' 



Stamens 4, in one row. 



Leaves opposite; stems creeping or floating. 



1. Isnardia. 

 Leaves alternate ; stems erect or ascending. 



' 2. Ludwigia. 



Stamens 8t12, in 2 rows. . , . 3, Jw&iaeq. 



Seeds furnished with a tuft of silky hairs. A. Ghamaetierion. 

 Calyx-tube prolonged beyond the ovary. 



Seeds furnished with silky hairs. 5. Epilobium. 



Seeds naked or sometimes tubereulate. ,: 



- Stamens equal in length. 



Ovules and seeds horizontal, inserted in 2 or rarely 



more rows, prismatic-angled. ■• 6.' Omagra: 

 Ovules and seeds ascending, not angled. 



7. Qengther/i. 

 Stamens unequal in length, the alternate ones longer. 

 ,:,r . i, ' " i 8j Kneiffia. 



Fruit indehiscent, nut jjke,. , , 9. Gqura* « 



Floral whorls of 2 parts. 10. Circaea, 



1. ISNABDIA L. 



1. Isnardia palustris L. Water Purslane. M. p. 652. Muddy ditches and 

 swamps. Summer and fall. 



2. LTOWIGIA L. 



Flowers inconspicuous; petals none,' 'or small, yellowish or greenish; valves 

 of the capsule separating from the terminal' disk. 



Capsules subglobose or top-shaped. i < 1. L. sphaerocarpa. 



Capsules cyiindrie or obpyramidal. 2. L. linearis. 



Flowers showy, peduncled ;., petals 4arge, bright yellow; capsules opening by 



an apical pore. 



".. ''■'■ Plahtis hirsute; capsules bristly-pubescent. 3. L. hirtella.' 



Plants glabrous or nearly so ; capsules glabrous. 4. L. alternifolia. 



1. Ludwigia sphaerocaepa Ell. M. p. 653. Swamps. Summer. 



Bucks— Bristol (Fr.). 



Burlington — Atsion. Gloucester — Near Mickleton Junction (He.). 

 Salem— Manington (O), Cumberland, Millville (Je.) (Be.).' Atlantic— 

 Hammonton (Cr.) (Ke.) (Pr.), Egg Harbor (Ja.), May's Landing (Le.). 

 -•■Cape May — Woodbine (Br.). Mercer— Mercerville (VP.). 

 1 New Castle— Townsend, Cariby and Tatnall. 



2. Ludwigia linearis Walt. M. p. 654. Swamps. Summer. 



Burlington— Atsion (Fr.). Cape May— Woodbine (St.). Atlantic— 

 Hammonton (Ke.), May's Landing (Li.), Egg Harbor (Wn.). 



3. Ludwigia hirtella Baf. M. p. 654. Moist pine-barrens. Summer. 



Burlington— Batsto, Quaker Bridge (C), Atsion (Fr.). Atlantic— 

 Hammonton, Main Boad Station (C.). 



4. Ludwigia alternifolia L. Seed-box. M. p. 654. Swamps. Summer. 



3. JUSSIAEA L. 



1. Jussiaba diffusa Forskl. M. p. 654. Ponds. Summer. 

 Camden— Kaighn's Point, Mart, and I. Burh (Fu.). 



