ALISMACEAE. 



VOL. I. 



16. Sagittaria subulata (L.) Buchenau. 

 Subulate Sagittaria. Fig. 246. 



Alisma Subulata L. Sp. PI. 343. 1753. 



Sagittaria pusilla Nutt. Gen. 2: 213. 1818. 



5. subulata Buchen. Abh. Nat. Ver. Bremen 2 : 490. 1871. 



Monoecious or rarely dioecious, scape very slender, 

 2'-6' high, few-flowered, about equalling the leaves. 

 Leaves all reduced to rigid phyllodia or sometimes 

 bearing linear or linear-lanceolate blades, i'-ii' 

 long ; bracts united or partly separated ; flowers 5"-8" 

 broad ; fertile pedicels reflexed, longer than the 

 bracts in fruit; stamens about 8; filaments about 

 equalling the anthers, dilated, glabrous ; achenes less 

 than i" long, obovate, with narrow wings, 2 or 3 

 crests on each side, sometimes crenate ; beak short. 



In tide-water mud, New York to Florida and Ala- 

 bama. July-Sept. 



17. Sagittaria lorata (Chapm.) Small. Thong- 

 leaved Sagittaria. Fig. 247. 



Sagittaria natans lorata Chapm. Fl. S. U. S. 449. 1860. 

 ^Sagittaria natans (f) gracillima S. Wats, in A. Gray, Man. 



Ed. 6, 556. 1890. 

 ?Sagittaria subulata gracillima J. G. Smith, in Mem. Torrey 



Club 5: 26. 1894. 

 Sagittaria lorata Small, N. A. Fl. if 1 : 52. 1909. 



Monoecious, scape elongate, i-3i long. Leaves with 

 bladeless petioles or blades when present floating, elliptic, 

 oblong or ovate-oblong, 7i"-25" long, rounded, subcordate 

 or hastate-truncate at the base ; phyllodia flattened, strap- 

 like; whorls one or several; bracts thin, acuminate; sepals 

 becoming \\"-2\" long; corolla fully 10" wide; achenes 

 \"-\\" long, with 5-7 prominently dentate or crenate crests, 

 the beak erect or curved upward. 



In ponds and streams, New Jersey to Florida. The form 5". natans gracillima (the fruit of 

 which is unknown) in Massachusetts and Connecticut. 



Butomus umbellatus L., a plant of the related family Butomaceae, with many-ovuled ovaries, 

 rose-colored flowers and narrow ensiform leaves, native of Europe and Asia, has been found on 

 the shores of the St. Lawrence River, near Montreal. 



Family 8. VALLISNERIACEAE Dumort. Anal. Fam. 54. 1829. 



TAPE-GRASS FAMILY. 



Submerged or floating aquatic herbs, the leaves various. Flowers regular, 

 mostly dioecious, appearing from an involucre or spathe of 1-3 bracts or leaves. 

 Perianth 3-6-parted, the segments either all petaloid or the 3 outer ones small 

 and herbaceous, the tube adherent to the ovary at its base in the pistillate flowers. 

 Stamens 3-12. Anthers 2-celled. Ovary i-celled with 3 parietal placentae. Styles 

 3, with entire or 2-cleft stigmas. Ovules anatropous or orthotropous. Fruit 

 ripening under water, indehiscent. Seeds numerous, without endosperm. 



About 6 genera and 25 species of wide distribution in warm and temperate regions. Besides 

 the following, another genus, Halophila, occurs on the coast of Florida. 



Stem branched ; leaves whorled or opposite. i. Philotria. 



Acaulescent ; stoloniferous ; leaves grass-like, elongated. 2. Vallisneria. 



i. PHILOTRIA Raf. Am. Month. Mag. 2: 175. 1818. 

 [ELODEA Michx. Fl. Bor. Am. i : 20. 1803. Not Elodes Adans. 1763.] 

 Stems submerged, elongated, branching, leafy. Leaves opposite or whorled, crowded, 

 i-nerved, pellucid, minutely serrulate or entire. Flowers dioecious or polygamous, arising 

 from an ovoid or tubular 2-cleft spathe. Perianth 6-parted, at least the 3 inner segments 

 petaloid. Staminate flowers with 9 stamens, the anthers oblong, erect. Ovary i-celled with 3 

 parietal placentae. Stigmas 3, nearly sessile, 2-lobed. Fruit oblong, coriaceous, few-seeded. 

 [Name from the Greek, referring to the leaves, which are often whorled in three's.] 

 About 10 American species. Type species Elodea canadensis Michx. 



