228 LYTHRACEiE. Ammannia. 



celled by the obliteration of the dissepiments, many-seeded. Seeds without 

 albumen. — Herbs, rarely shrubs or trees, with usually 4-sided branches, and 

 opjjosite leaves which are destitute of stipules and dots. Flowers mostly 

 axillary. 



CONSPECTUS OF THE GENERA. 



1. Ammannia. Calyx campanulate. Petals small. Style short. Capsule globose or ovoid. 

 3. Lythrdm. Calyx cylindrical. Petals conspicuous. Style filiform. Capsule oblong. 



3. Decodon. Calyx campanulate ; the accessory teeth spreading and elongated. Stamens 10 ; five of them much 



exserted. Petals large and showy. Style filiform. Capsule globose. 



4. CtJPHEA. Calyx tubular or ventricose. Petals unequal. Stamens included. Capsule oblong. 



1. AMMANNIA. Houst.; La7n. ill. t. 77; Endl. gen. 6146. ammannia. 



[ Named in honor of John Ammann, a Russian botanist of the last century.] 



Calyx campanulate, 4 - 5-toothed or lobed ; the sinuses usually expanding into teeth or horns. 

 Petals often wanting. Stamens as many, or sometimes twice as many as the lobes of the 

 calyx. Ovary 2 - 4-celled. Style mostly short : stigma capitate. Capsule globose or 

 ovoid, included in the calyx, either bursting transversely or opening by valves. Seeds 

 numerous, attached to thick central placentce. — Herbaceous, mostly smooth annual plants, 

 destitute of beauty, growing in wet places, with square stems and opposite entire leaves. 

 Flowers small, axillary, sessile or somewhat peduncled, bracteolate : petals small. 



§ Ammannia proper. Arnott. Flotcers iciramerous : lobes of the calyx with as many small inter- 

 mediate horn-like processes : capsule ^-celled. 



1. Ammannia humilis, Michx. Dwarf Ammannia. 



Stem branched from the base, ascending ; leaves linear-oblong or lanceolate, obtuse, tapering 

 at the base into a short petiole ; flowers solitary in the axils of the leaves, closely sessile ; 

 style very short, or almost none. — Michx. jl. l.p. 99; Ell. sk. I. p. 218; Torr.fl. \.p. 189; 

 Bigel. jl. Bost. p. 53 ; DC. prodr. 3. p. 79. A. ramosior, Linn. sp. 1. p. 120 ; Walt. jl. 

 Car. p. 88, not of Linn. mant. and subsequent authors. 



Stems 4-8 inches high, sometimes almost simple, of a reddish color, nearly terete below, 

 somewhat 4-sided above, rather slender. Flowers with 2 small subulate bracts at the base. 

 Calyx quadrangular, &-toothed ; the 4 intermediate (accessory) teeth shorter and spreading, 

 rather obtuse ; the others erect and acute. Petals white or pale purple, orbicular, inserted 

 opposite the shorter teeth of the calyx, caducous. Ovary turbinate. Style very short, but 

 distinct : stigma capitate. Capsule quadrangular, short and thick ; the cells many-seeded. 



Wet places ; about three miles from Brooklyn, on Long Island. August. 



