ALISMACEAE. 



Vol. I. 



i. Echinodorus radicans (Nutt.) 

 Engelm. Creeping Bur-head. Fig. 225. 



Sagittaria radicans Nutt. Trans. Am. Phil. Soc. 



(II.) 5: 159. 1833-37- 

 Echinodorus radicans Engelm. in A. Gray, Man. 



Ed. 2, 438. 1856. 



Leaves coarse, ovate, obtuse, cordate, 2'-8' 

 long, ii'-y¥ wide, marked with short pellucid 

 lines, nerves 5-9; cross-veins netted. Petioles 

 sometimes 20' long; scapes creeping, 2°-4° 

 long, scabrous, often rooting at the nodes ; 

 verticils distant; bracts linear-lanceolate, acu- 

 minate, dilated at the base; pedicels 3-12, 

 unequal, i'-2i' long, slender; sepals persistent, 

 shorter than the heads; petals larger, obovate, 

 about 3" long; stamens about 20; style shorter 

 than the ovary; achenes numerous, about 2" 

 long, 6-10-ribbed, with 2-several oval glands 

 on each side and beaks about one-fourth their 

 length ; fruiting heads 4" in diameter. 



In swamps, Illinois to North Carolina and 

 Florida, west to Missouri and Texas. June-July. 



2. Echinodorus cordifolius (L.) Griseb. 

 Upright Bur-head. Fig. 226. 



Alisma cordifolia L. Sp. PI. 343. 1753. 

 Echinodorus rostratus Engelm. in A. Gray, Man. 



Ed. 2, 538. 1856. 

 Echinodorus cordifolius Griseb. Abh. Kon. 



Gesell. Wiss. Gott. 7: 257. 1857. 

 Echinodorus cordifolius lanceolatus Mack. & 



Bush; Fl. Jackson Co. 10. 1902. 



Leaves various, ovate, obtuse, cordate, 6'-8 / 

 long and wide, in smaller plants sometimes 

 lanceolate, acute at each end, i'-V long; pe- 

 tioles angular, striate, i'-io' high ; scapes 1 or 

 more, erect, s'-i6' tall ; flowers 3^6 in the ver- 

 ticils; pedicels i'-i' long, erect after flowering; 

 bracts linear-lanceolate, acuminate, dilated at 

 the base; sepals shorter than the heads; petals 

 2"-3" long; stamens often 12; styles longer 

 than the ovary ; fruiting heads bur-like, a"-3" 

 in diameter; achenes li" long, narrowly obo- 

 vate or falcate, 6-8-ribbed ; beak apical, half 

 the length of the achene. 



In swamps and ditches, Illinois to Florida, 

 west to Missouri and Texas. Also in tropical 

 America. June-July. 



4. LOPHOTOCARPUS T. Durand, Ind. Gen. Phan. X. 1888. 



. [Lophiocarpus Miquel, Fl. Arch. Ind. 1 : Part 2, 50. 1870. Not Turcz. 1843.] 

 Perennial, bog or aquatic herbs with basal long-petioled sagittate or cordate leaves, simple 

 erect scapes bearing flowers in several verticils or 2-3 at the summit, the lower perfect, the 

 upper staminate. Sepals 3, distinct, persistent, erect after flowering and enclosing or enwrap- 

 ping the fruit. Petals white, deciduous. Receptacle strongly convex. Stamens 9-15, hypo- 

 gynous, inserted at the base of the receptacle. Filaments flattened. Pistils numerous; ovule 

 solitary, erect, anatropous; style elongated, oblique, persistent. Achenes winged or crested. 

 Embryo horseshoe-shaped. [Greek, signifying crested fruit.] 



About 7 species, the following of eastern North America, the others in the Southern States, 

 California and tropical America. Type species : Sagittaria calycina Engelm. 



Leaves hastate or sagittate ; plants of fresh-water ponds or marshes. 



Leaves with large basal lobes fully as long as the terminal one. i. L. calycinus. 



Leaves with small basal lobes shorter than the terminal lobe. 2. L. depauperatus. 

 Leaves imperfect or obsolete, the phyllodia thick or partially flattened ; plants of salt or brackish 

 water. 



Phyllodia terete or nearly so, prominently nodose-septate. 3, £,. spongiosus. 



Phyllodia flat, more or less spatulate, not prominently nodose. 4] L. spathulatus. 



