238 ONAGRACEvE. Ludwigia. 



Michx. fl.l. p.89; Pursh, fl.l. p.UO; Torr. fl.\.p.\SO; Bart. ft. N. Am. 1. t. 14. 

 Isnardia alteniifolia, DC. prodr. 3. p. 122 ; Beck, hot. p. 119; Darlingt. Jl. Cest. p. 109. 



Perennial. Stem 2-3 feet high, slightly pubescent or almost smooth, purplish, much 

 branched, marked with elevated lines descending from the bases of the petioles. Leaves 

 2-4 inches long, the lateral veins uniting so as to form a continuous line within the margin. 

 Pedicels 2-4 lines long. Bracteoles lanceolate, acute, situated close to the flower. Calyx- 

 segments longer than the ovary, becoming purple on the inside. Petals yellow, roundish- 

 obovate, caducous. Stamens much shorter than the petals : anthers large, oblong. Style 

 thick : stigma obscurely 4-lobed. Capsule globose-cubical, crowned with the large dilated 

 base of the style, opening at first by a small hole left by the separation of the deciduous style ; 

 afterward, the summit (stylopodium) of the capsule falls off. Seeds very numerous, attached 

 to a large central placenta. 



In swamps ; common. July - August. 



2. Ludwigia sph^rocarpa, Ell. (Plate XXIX.) Round-fruited Ludioigia. 



Whole plant nearly smooth ; stem erect, much branched ; leaves narrowly lanceolate, 

 mostly acute, attenuate at the base ; flowers solitary, axillary, or clustered towards the summit 

 of the branches, and appearing as if in leafy interrupted spikes, apetalous ; bracteoles minute 

 or wanting ; lobes of the calyx as long as the capsule, triangular-ovate ; capsules turbinate- 

 globose, obscurely 4-sided, canescent, crowned with the deeply 4-lobed stylojjodium. — Ell. 

 sk. 1. p. 211 ; Torr. <^- Gr.fl. N. Am. \. p. 524. Isnardia sphaerocarpa, DC. prodr. 3. p. 61. 



Perennial. Stem about 2 feet high, slightly pubescent above, smooth below, of a reddish 

 tinge. Leaves of the stem 3-5 inches long, of the branches about 2 inches, remotely and 

 obscurel}? repand-denticulate with a long tapering base, nearly smooth ; the veins confluent 

 near the margin. Flowers in somewhat compound leafy spikes. Calyx pubescent ; the 

 segments a little spreading. Petals none. Stamens scarcely half the length of the sepals : 

 anthers broader than long ; the lobes rather remote. Stigma oval, not lobed. Capsule about 

 2 lines long, crowned with the reddish depressed stylopodium, which is deeply divided into 4 

 obtuse lobes. Seeds oval. 



In water near Peekskill (Mr. R. I. Browmie). July - August. 



^2. Isnardia, Linn. Leaves opposite, mostly petioled : flowers sessile : petals very small or none : 



capsules short, truncate at the apex. 



3. Ludwigia palustris. Ell. Water Purselane. 



Plant smooth and slightly succulent ; stems procumbent, rooting or floating at the base ; 

 leaves ovatc-spatulate, shining, tapering into a slender petiole ; flowers axillary, apetalous, 

 or with small purplish petals ; lobes of the calyx very short ; capsules oblong, 4-sided, not 

 attenuate at the base. — Ell. sk. 1. p. 214 ; Torr. <J- Gr. Jl. N. Am. 1. p. 525. L. apetala, 

 Walt.fl. Car. p. 89. L. nitida, Michx. Jl. 1. p. 87 ; Pursh,Jl. l.p. 111. Isnardia palustris, 



