ALISMACEAE 



805 



413. SAGITTA X RIA, L. 



[Latin, Sctffitta, an arrow; from the prevailing form of the leaves.] 

 Flowers monoicous, the staminate ones above. Petals orbicular, 

 imbricated in the bud. Stamens numerous; anthers extrorse. 

 Ovaries many, in depressed-globose heads, becoming flatted winged 

 nkenes, in fruit. Smoothish perennials; roots often tuberiferous ; 

 leaves polymorphous, usually sagittate ; scape simple ; flowers in 

 verticils of 3, pedicellate and bracteate. 



1. S. varicibiliM, Engelmann. Leaves varying from broad-ovate, 

 or linear, and sagittate, to narrow-lanceolate and not sagittate. 

 H. sagittifolia. L. $ Fl. Cestr. ed. 2. p. 528. 

 Alto, S. heterophylla, Purth. $ FL Cestr. ed. 2. p. 529. 

 VARIABLE SAGITTARIA. Arrow-head. 



Tubers (or rhizomas) ova!, 1 to 2 inches in diameter. Leaves 3 or 4 to 10 or 12 

 inches long, usually more or legs ovate; petioles 4 to 12 or 15 inches in length, 

 tapering upwards. Scape 9 to 18 inches high. Verticils of flowers numerous. 

 Heads of fruit ^ to % of an inch in diameter. 

 Jfab. Swampy springs ; ditches, &c. : frequent. Fl. July. Fr. Sept. 



Obs. Hogs are fond of the tubers of this plant, and soon dis- 

 figure a meadow, where they abound, by rooting for them. KALM 

 says, the Indians and Swedes called the plant "Katniss;" and that 

 the tubers were sometimes "as big as a man's fist:" that when 

 roasted, they tasted well, but were rather dry. See Travels. VoL 

 2,^96-7. 



ORDER CIV. HYDROCIIARIDACEAE. 



Aquatic Jierbs ; leaves sometimes verticillate, or opposite, usually radical ; flowers 

 l>olygamous, or dioicous, regular, often on scape-like peduncles from a kind of 

 rpathe ; floral envelopes mostly double, in the pistillate flowers coalesced into a 

 tube, and adherent to the ovary; stamens 3 to 12, distinct, or monadelphous ; fruit 

 utricular, coriaceous, or fleshy, indehiscent; seeds ascending; embryo straight, 

 without albumen. 



414. DO R A, JffuUaU. 

 [Gr. Hydor, or Udor, water; from its place of growth,] 



Flowers polygamo-dioicous, solitary; from a sessile tubular bifid 

 nxillary spathe. STAM. FL. minute ; perianth 6-parted (viz. tepals 

 and petals each 3, oval, and nearly alike colored); anthers 9, oval, 

 tmbsessile. PERFECT FL. perianth extended beyond the ovary into 

 ;i long and very slender tube, the lobes (or sepals and petals) obovate, 

 spreading; anthers usually 3, oblong, opposite the outer lobes of 

 the perianth. Ovary 1-celled, with 3 projecting parietal placentae ; 

 tfyle capillary, coherent with the tube of the perianth ; stigmas 3, 

 large, 2-lobed, exserted. Fruit oblong, coriaceous, few-seeded. 

 Annual? smooth; stem filiform, dichotomously branched; leaves 

 verticillate, or opposite, immersed and pellucid. 



1. U. Canadensis, Nutt. Leaves mostly verticillate in threes, 

 ovate-oblong, or lance-linear, finely serrulate. 

 CANADIAN UDORA. 



Stem 3 or 4 to 8 or 10 inches long (varying with the depth of water), diffusely 

 branching. Leaves 2 to 6 lines long, nerveless, light green and shining, the 



