146 EVENING-PRIMROSE FAMILY. 



T. grandifl6ra. Marshes S. : hairy, with stems erect from a creeping 

 base, lanceolate acute leaves, flowers 2' in diameter, the 5 calyx lobes only half 

 as long as the petals, and pods cylindrical and stalked. 2/ 



J. ripens. In water from S. 111. S. : smooth, with creeping or floating 

 and rooting stems, oblong leaves tapering into a slender petiole, long-peduncled 

 flowers 1' or more across, with 5 calyx-lobes, the cylindrical or club-shaped pods 

 tapering at the base. ^ 



9. LUDWIGIA, FALSE LOOSESTRIFE. (Named for C. G. Ludwin, 

 a German botanist, rather earlier than Linnaeus.) Marsh herbs, with entire 

 leaves ; flowers seldom handsome, in summer and autumn. 2/ 



1. Leaves alternate, mostly sessile. 



* Flowers peduncled in the upper axils, with yellow petals (about $' long) equalling 



the leaf-Like ovate or lance-ovate calyx-lobes : stamens and styles slender : 

 pud cubical, strongly 4-angled, opening by a hole at the top : sterna 2 - 3 It igh . 



L. alternifdlia. Common E., the only one found far N. : smoothish, 

 branching, with lanceolate leaves tapering to both ends, petals scarcely longer 

 than calyx, and angles of pod wing-margined. 



L. virgata. Fine barrens S. : downy, with mostly simple stems, blunt 

 oblong leaves or the upper linear and smaller, and petals twice the length of the 

 reflexed calyx. 



L. hirtalla. Pine-barrens from New Jersey S. : hairy, with simple stcm% 

 oblong or lanceolate short and blunt leaves, and petals twice as long as the 

 barely spreading calyx-lobes. 



* * Flowers sessile in the upper axils, small, and with pale, ydlow petals about the 



length of the persistent caly.r-/obes : stamens and style short: leaves on 

 flowering stems narrow and 'linear. 



L. lipearis. Swamps from N. Jersey S. : smooth, loosely branched, 1 -3 

 high, with acute leaves on the flowering stems, but obovate ones on creeping 

 runners ; pods oblong-clubshaped or top-shaped and much longer than the tri- 

 angular-ovate calyx-lobes. 



L. linifdlia, only S., is 6' -12' high, with blunter leaves, and cylindrical 

 pods little longer than the lanceolate calyx-lobes. 



* # * Flowers sessile, often clustered, and with no petals, or rarely mere rudi- 



ments : leaves mostly lanceolate, some species with obovate or spatulate leaves 

 on creeping runners: flowering stems mostly 2 -3 high. 

 *- Downy all over: flowers spiked or crowded at the end of the branches. 

 L. pildsa. Only S. : much branched, with lance-oblong leaves, and glob- 

 ular-4-sided pod about the length of the spreading calyx-lobes. 



* *- Smooth or smoothish throughout. 



L. cylindrica. From Illinois and N. Car. S. : much branched, with long 

 lanceolate and acute leaves tapering into a petiole, .small axillary flowers, and 

 cylindrical pods much longer than the small calyx-lobes. 



L. sphserocarpa. From E. New England S. : with lanceolate or linear 

 leaves acute at both ends, very small flowers in the axils, and globular pods not 

 longer than the calyx-lobes, with hardly any bractlcts at their base. 



L. polycarpa. From Michigan S. : like the last, but smoother, and with 

 conspicuous slender bractlets at the base of the 4-sided rather top-shaped pod, 

 which is longer than the calyx-lobes. 



L. capitata. From N. Carolina S. : with slender simple stems angled 

 towards the top, long lanceolate leaves ; flowers mostly crowded in an oblong or 

 roundish terminal head, and obtusely 4-angled pod longer than the calyx-lobes. 



L. alata. From N. Carolina S. : with simple or sparingly branched stems 

 strongly angled above, few flowers, in the axils of the upper* wedge-lanceolate 

 leaves, and an inversely pyramidal pod as long as the white calyx-lobes, with 

 concave sides and winged angles. 



L. microcarpa. From N. Carolina S. : the low stems creeping at base 

 nnd 3-anglcd above, leaves spatulate or obovate, with minute flowers in their 

 axils, the short 4-anglcd pods not larger than a pin's head. 



