Genus 2. 



BUCKBEAN FAMILY. 



2. Nymphoides aquaticum (Walt.) 



Kuntze. Larger Floating Heart. 



Fig. 3372. 



Anonymos aquatica Walt. Fl. Car. 109. 17S8. 

 Villarsia aquatica Gmel. Syst. 1: 447. 1791. 

 Menyanth.es trachyspcrma Michx. Fl. Bor. Am. 1 : 



126. 1803. 

 Limnanthemum trachyspermum A. Gray, Man. Ed. 



5, 390. 1867. 

 Limnanthemum aquaticum Britton, Trans. N. V. 



Acad. Sci. 9 : 12. 1889. 

 Nymphoides aquaticum Kuntze, Rev. Gen. PI. 



429. 1891. 



Similar to the preceding species but stouter 

 and larger. Floating leaves cordate-orbicular, 

 thick, entire or repand, 2'-6' long, spongy, and 

 with the petioles and stolons densely covered 

 with minute pits ; primary leaves spatulate ; 

 pedicels slender, 1-3' long; tubers linear- 

 oblong, thicker ; corolla white, 6"-io" broad ; 

 style none ; seeds rough ; capsule longer than 

 the calyx. 



In ponds, southern New Jersey and Delaware 

 to Florida and Texas. May-Aug. 



3. Nymphoides nymphaeoides (L.) 



Britton. Water Lily. Floating 



Heart. Fig. "3373. 



Menyanthes nymphaeoides L. Sp. PI. 145. 1753. 



Limnanthemum nymphaeoides Hoffm. & Link, 

 Fl. Port. 1 : 344. 1809. 



Stems long, stout, creeping or buried in 

 the mud, ascending to the surface of the 

 water, branched, the upper nodes bearing 

 a petioled leaf and a cluster of flowers, or 

 the upper internodes very short and their 

 leaves apparently opposite. Petioles stout, 

 mostly longer than the ovate-orbicular firm 

 blades, which are 2'-4' broad ; pedicels 

 stout, becoming 3'-6' long, not accompanied 

 by tufts of tubers ; flowers bright yellow, 

 I in diameter, or more ; corolla segments 

 short-fringed ; seeds with fimbriate margins. 



Naturalized in ponds, District of Columbia. 

 Native of Europe and Asia. May-July. 



Family 17. APOCYNACEAE Lindl. Nat. Syst. Ed. 2, 299. 1836. 



Dogbane Family. 

 Perennial herbs, shrubs, vines, or some tropical genera trees, mostly with an 

 acrid milky juice, with simple' opposite alternate or verticillate exstipulate leaves, 

 and perfect regular 5-parted cymose solitary or paniculate flowers. Calyx infe- 

 rior, persistent, the lobes imbricated in the bud. Corolla gamopetalous, its lobes 

 convolute in the bud and often twisted. Stamens as many as the lobes of the 

 corolla, alternate with them, inserted on the tube or throat ; anthers linear-oblong, 

 or sagittate, 2-celled; pollen-grains simple, often glutinous. Ovary superior, or 

 its base adherent to the calyx, of 2 distinct carpels, or 1 -celled, with 2 parietal 

 placentae, or 2-celled ; ovules few or numerous, anatropous or amphitropous ; style 

 simple, or 2-divided ; stigma simple. Fruit usually of 2 follicles or drupes. Seeds 

 often appendaged by a coma : endosperm fleshy, not copious ; embryo straight ; 

 cotyledons flat or concave ; radicle terete, usually shorter than the cotyledons. 



About 130 genera and n 00 species, very widely distributed, mostly in tropical regions. 



Leaves alternate ; erect herbs. 1. Amsonia. 

 Leaves opposite ; vines or herbs. 



Flowers large, axillary, solitary. 2. I'inca. 



