104 OXAGKACK-K. (KVKMXO-I'Uni IJi iSE FAMILY.) 



0. J. hirta, Vahl. Slinihby, hirsute; branches terete; leaves l)roadly 

 hiiifpohito, acute at cacli cud ; ovary chxvate, jis long as tlie 2-)>racte(i jicdiccl ; 

 calyx lolios 4, ovate-lanceolate, acuminate, longer than the tube, sliorter than 

 the roundish petals ; capsule davate-oblong, ol)scurely 4-sided, longer than 

 the bracts. — Muddy bauks of rivers. South Florida. — Shrub 5°-lO° 

 high. 



5. LUDWIGIA, L. Skku-hox. 



Calyx tube 4-angled or cylindrical, mostly short, not prolonged beyond the 

 ovary. I'etals 4, roundish or obcordate, often wanting. Stamens 4. Style 

 short. Stigma capitate. Capsule variously deliisccnt, 4-cclIcd, many-seeded. 

 — Perennial and mostly stoloniferous marsh herbs, with entire leaves, and 

 yellow flowers. 

 » Capsule cubical, indehiscent , discharging the seeds through a central pore of 



the convex disk: calyx lobes deciduous : petals large: stamens and style 



slendir: Icares alternate: flowers pedicelled. 



1. L. alternifolia, L. Smoothish; stem much branched ; leaves lanceo- 

 late, short])eti()led, acute ; calyx lobes spreading, al)out as long as the petals ; 

 capsule large, wing-angled. — Shady swamps. August. — Stem 2° -3° high. 

 Flowers axillary, or the upper ones somewhat racemed. 



2. L. virgata, Michx. Tomentose ; stem slender, simple, or branching 

 from the base ; leaves obtuse, sessile, the lowest oblong, the uppermost linear; 

 flowers in elongated leafy racemes; petals twice as long as the reflexed calyx 

 lobes; capsule strongly 4-augled. — Low pine barrens, sometimes in rather 

 dry places. July -August. — Stem 2° -.3° high. Varies considerably in 

 pubescence, and in size of the flowers and capsule. 



3. L. hirtella, Raf. Hairy ; stem slender, sinijde or s])aringly branched ; 

 leaves short, lanceclate or oblong, obtuse, sessile and rounded at the base ; 

 flowers axillary ; petal: twice as long as the erect or spreading calyx lobes ; 

 capsule strongly angled. — Flat pine barrens. August. — Stem 2° - 3° high. 

 * * Valves of the capsule separating from the concave disk, and irregularly 



from the persistent partitions and placenta : calyx lobes persistent : petals 

 small m- none : stamens and style short: stems erect or ascending: leaves 

 alternate : flowers sessile. 



-t— Petals conspicuous. 



4. L. linearis, Walt. Smooth; stem (l°-3° high) virgately much 

 branched; leaves linear, acute ; flowers small; capsule clavate-oblong, wiih 

 4 rcjuiided angles. 2-3 times as long as the triangular-ovate calyx lol)es. — 

 Ditches and ponds in tlie lower districts. July -Sept. — Bark at the base 

 of the stem spongy. 



•5. L. linifolia, Poir. Smooth; stem low (6' -12'), creeping at the base, 

 branching; leaves linear or linear-spatulate, often obtuse; capsule linear- 

 cylindrical, rather longer than the lanceolate calyx lobes. — Ditches and swamps 

 in the lower districts. July - Sept. 



-I— -i— Petals minute or wanting. 



6. L. cylindriea, Ell. Smooth ; stem angled above, often much 

 branched ; leaves long, lanceolate, obscurely denticulate, acute, tapering into 



