LlMNANTHEMUM. 



GENTIANACEiE. 



115 



8. LlMNANTHEMUM. S. P. Gmel. in act. acacl. Petrop. 15. p. 567. t. 17. /. 2 (1769), 



ex Endl. ; Griseb. Gent. p. 341. 



Villarsia, Vent., R. Br., Endl. Villarsia & Limnanthemum, Griescb. 



[ From the Greek, limnos, a marsh, and anthcrnon, a flower ; in allusion to its place of growth.] 



Calyx 5-parted. Corolla somewhat rotate, 5-parted ; the lobes bearded or scaly at the base ; 

 the upper part usually smooth. Stamens 5, alternating with five glands which are inserted 

 in the throat of the corolla. Ovary roundish ; the sutures not introflexed : ovules rather 

 numerous or few. Style single or none : stigma small, 2-lobcd. Capsule one-celled, 2- 

 valved, or obscurely valved and opening (regularly or irregularly) only in decay. Seeds 

 rather numerous or few — Floating or marsh plants, with simple, often cordate or somewhat 

 peltate leaves. Flowers in fasciculate umbels, either produced from the upper part of the 

 petiole near the leaf, or forming a terminal panicle, yellow or rarely white. 



1. Limnanthemum lacunosum, Griseb. Floating Heart. 



Floating ; leaves reniform- cordate, smoothish above, spongy -rough underneath, deeply 

 cloven at the base ; flowers (white) fasciculate, produced from the petiole near the leaf ; 

 glands of the corolla stipitate ; style none ; capsule scarcely as long as the calyx ; seeds 

 muricate. — Griseb. in Hook. Jl. Bor.-Am. 2. p. 71, and Gent. p. 347. Villarsia lacunosa, 

 Vent, choix, p. 9 ? ; Torr. Jl. 1. p. 214 ; Bigel. Jl. Bost. p. 78, excl. syn. ? ; Graham in 

 Edinb. new phil. jour. Oct. 1828. V. cordata, Ell. sk. 1. p. 215. 



Stem prostrate and rooting in mud at the bottom of the water, about as thick as a goose- 

 quill. Leaves about an inch long, rather fleshy, exactly cordate or somewhat reniform ; the 

 sinus at the base either narrow or open, very entire or obscurely crenate : lobes somewhat 

 acute, bright green above, and variegated with white spots ; the lower either pale or purplish, 

 roughened with minute spongy granulations : petiole elongated according to the depth of the 

 water, bearing about half an inch below the leaf a cluster of unequal one-flowered peduncles, 

 and (usually) a number of slender conical (often elongated) root-like tubers which are capable 

 of producing new plants. One or more of the flowers rise above the surface at a time, and 

 fade in a day or two ; then ripen their fruit under water. Calyx deeply 5-parted ; the segments 

 ovatedanceolate, rather acute. Corolla pure white, about one-third of an inch in diameter ; 

 the segments obovate, slightly emarginate, undulate on the margin ; the central part pubescent 

 in lines near the extremity : throat yellow. Stamens less than half the length of the corolla, 

 and inserted into its tube : anthers oblong : glands alternating with the stamens, and inserted 

 lower down, yellow, hairy. Ovary ovoid, a little compressed, surrounded at the base with a 

 5-lobed glandular disk : stigma small, 2-lobed. Capsule covered with the connivent calyx- 

 lobes, ovoid : placentae 2 (rarely 3), each bearing 6-10 roundish compressed rough seeds. 



Ponds and lakes ; frequent. July - August. The germination of this plant is very re- 



15* 



