GENUS 2, BUCKBEAN FAMILY. 19 
2. Nymphoides aquaticum (Walt.) 
Kuntze. Larger Floating Heart. 
Fig. 3372. 
Anonymos aquatica Walt, Fl. Car. 109. 1788. 
Villarsia aquatica Gmel, Syst. 1: 447. 1791. 
Menyanthes trachysperma Michx. Fl. Bor. Am, 1: 
126, 1803. 
Limnanthemum trachyspermum A. Gray, Man. Ed. 
5, 390. 1867. 
Limnanthemum aquaticum Britton, Trans. N, Y. 
Acad. Sci. g: 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’-10” 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. Pl. 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. FPetioles 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, 
, 
1’ 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. 
DocBaneE Famity. 
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 superidr, 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 1100 species, very widely distributed, mostly in tropical regions. 
Leaves alternate ; erect herbs. 1. Amsonia, 
Leaves opposite ; vines or herbs. ; 
Flowers large, axillary, solitary. 2. Vinea, 
