056 ALISMACE^. (water-plantain FA3IILY.) 



crested. (S. pusilla, Parsh.) — In mud or sliallow water, near the coast; 

 N. Y. to ria. 



Var. (1) gracillima, Watson. Scape and the almost or wholly bladeless 

 leaves very slender and greatly elongated (2-4° long, V wide) ; pedicels all 

 elongated, in usually distant whorls, the lower pistillate, slender and spread- 

 ing ; fruit unknown. (S. natans, Engelm. in Torr. Bull. ix. 4.) — In deep water 

 of streams in E. Mass. {Hitchings, Boott, C. E. Faxon, etc.) Wholly sub- 

 merged, only 1 or 2 flowers appearing at a time, floating on the surface. The 

 fruit, maturing under water, has not yet been collected. 



§2. LOPHIOCARPUS. Fertile Jiowers perfect; stamens 9-15, af the base 

 of the receptacle; sepals erect and emhracing the fruit. 



7. S. calycina, Engelm. Scaj^e weak (3 - 9' high), at length mostly pro- 

 cumbent'; usually only the lowest Avhorl fertile, with pedicels as long as those 

 of the sterile flowers, recurved in fruit ; bracts orbicular, obtuse or rarely pointed ; 

 filaments slightly rough, as L»;.g as the anthers ; achenes obovate with a short 

 horizontal style; leaves broadly halberd-shaped, obtuse or acutish, with wide 

 spreading lobes, often Avider than long, or lanceolate or sometimes reduced to 

 linear phyllodia. — Maine to Del., west to Wise, Mo., and Tex. Quite vari- 

 able, several forms being enumerated, as var. spongi6sa, with spongy texture 

 and bladeless submerged leaves, eastward ; and westward, var. FLtiXAXs, with 

 lance-linear floating leaves. 



3. ECHINODORUS, Richard. 



Flowers perfect. Petals imbricated in the bud. Stamens 6-21 or more. 

 Ovaries several or many, imbricated in a head, forming thick and ribbed 

 achenes in fruit, often beaked with a projecting persistent style. — Mostly 

 annuals, with the habit of Sagittaria, the naked stems sparingly branched or 

 simple, and the flowers on rather short pedicels, in whorls of .3-6 or more. 

 Fl. summer and autumn. (Name from €xii^(*>Svs, prichly, or from ix^'^'^^y ^^^ 

 Sopos, a leathern bottle, applied to the ovary, Avhich is in most species armed 

 with the persistent style, so as to form a sort of prickly head of fruit.) 



1. E. parvulus, Engelm, Scapes 1 -3' high; shoots often creeping and 

 proliferous; leaves lanceolate or spatidate, acute (^-l^' long, including the 

 petiole); umbel single, 2-8-flowered; pedicels reflexed in fruit; flower 3" 

 broad ; stamens 9 ; styles much shorter than the ovary ; achenes beakless, ob- 

 tusely few-ribbed. — In mud, Mass. to Mich, and E. Minn., south to Fla. and 

 Tex."' (S. Am.) 



2. E. rostratUS, Engelm. Scape erect, 3' -2° high, longer than the 

 leaves; leaves broadly ovate, cordate or truncate at base, obtuse (the blade 1-3' 

 long) ; umbel proliferous, in a branched panicle ; flower 5" broad ; stamens 12 ; 

 styles longer than the ovary ; achenes beaked, acutely many-ribbed. — Swamps 

 and ditches. 111 to Fla., Mo., and Tex. — A low form (var. laxceol\tus, 

 Engelm.) has the leaves lanceolate with an acute base. 111., Mo. 



3. E. radicans, Engelm. Stems or scape prostrate, creeping {2 -4° long), 

 proliferous, bearing many whorls of flowers; leaves somewhat truncately 

 broadly heart-shaped, obtuse (2 - 8' broad), long-petioled ; flowers 6 - 9" broad ; 

 stamens about 21 ; styles shorter than the ovary ; achenes short-beaked, the keeled 

 back denticulate. — Swamps, 111. to N. C. and Fla., west to Mo. and Tex. 



