580 



LYTHRACEAE. 



Vol. II. 



calyx-tube, the longer exserted. Style filiform; stigma small. Capsule globose, 3-5-ceIled, 

 included in the calyx, loculicidally dehiscent. [Greek, ten-toothed, referring to the calyx.] 

 A monotypic genua of eastern North America. 



I. Decodon verticillatus (L.) Ell. Swamp Loosestrife or Willow-herb. 



Fig. 3003. 



Lythrttm verlicitlatum L. Sp. PI. 446. 1753. 

 Decodon aquaticus J. F. Gmel. Syst. 2: 6yj. 1791, 

 Decodon verticillatus Ell. Bot. S. C. & Ga. i ; 544. 1821. 

 Nesaea verticvillata H.B.K. Nov. Gen. 6: 191. 1823. 



Aquatic, perennial, somewhat woody, with angular 

 recurved glabrous or slightly pubescent stems 3°-l0° 

 long, which root from the tip when they reach the 

 water or mud. Leaves lanceolate, z'-s' long, 4"-i2" 

 wide, glabrous above, somewhat pubescent beneath, 

 acute at both ends; petioles 2"-4" long; cymes sev- 

 eral-flowered; flowers nearly i' broad; petals cuneate 

 at the base, pink-purple ; filaments of the longer 

 stamens very slender ; capsule about 2i" in diameter. 



In swamps, Maine to Florida, west to southern On- 

 tario, Minnesota, Tennessee and Louisiana. Stems 

 clothed with parenchyma at the base. Flowers rarely 

 double. Ascends to 2000 ft. in Pennsylvania. July- 

 Sept. Peat- or slink-weed. Wild oleander. Grass-poly. 

 Milk willow-herb. 



Lagerstroemia indica L., crape myrtle, a large shrub 

 with terminal panicles of showy white to purple irregular 

 flowers, native of the East Indies is sparingly escaped 

 from cultivation from Maryland southward. 



5. LYTHRUM L. Sp. PI. 446. i753- 

 Herbs or shrubs, with 4-angled stems, opposite alternate or rarely verticillate entire 

 leaves, and solitary cymose-paniculate or spicate and terminal often dimorphous or trimor- 

 phous flowers. Calyx-tube cylindric, 8-12-ribbed, straight, not gibbous at the base, with 

 4-6 primary teeth and an equal number of appendages in the sinuses. Petals 4-6, usually 

 obovate, rarely wanting. Stamens 4-12, inserted on the calyx-tube, included or exserted. 

 Ovary oblong, sessile, 2-celled; style filiform; stigma mostly capitate; ovules numerous. 

 Capsules enclosed by the calyx, membranous, 2-celled, 2-valved, or bursting irregularly. 

 Seeds flat or angular. [Greek, gore, from the purple color of the flowers.] 



About 30 species, of wide geographic distribution. Besides the following, about 5 others occur 

 in the southern and western United States, Type species : Lythrum Salicaria L. 

 Flowers axillary, solitary ; stamens not more numerous than petals. 

 Leaves mostly alternate. 



Leaves obtuse ; stamens all included ; annual. i. L. Hyssopifolia. 



Leaves acute ; stamens of short-styled flowers exserted ; perennial. 2. L. alatum. 



Leaves mostly opposite, narrowly linear, narrowed at the base. 3. L. lineare. 



Flowers in spicate panicles, terminal ; stamens twice as many as petals. 



I. Lythrum Hyssopifolia L. Hyssop Loose- 

 strife. Grass Poly. Fig. 3004. 



Lythrum Hyssopifolia L. Sp. PI. 447. 1753. 



Annual, glabrous, pale green, erect or assurgent, at 

 length widely branched, 6-24' high. Leaves sessile, 

 mainly alternate, the lowest sometimes opposite, oblong 

 or linear-oblong, obtuse at the apex, rounded at the 

 base, 4"-io" long, i"-4" wide, those of the main stem 

 larger than those of the branches; flowers solitary and 

 sessile in the axils, not dimorphous, pink-purple, about 

 *" broad; petals nearly erect; stamens all included; 

 calyx 2J"-3" long in fruit. 



Borders of marshes, Maine to New Jersey and Pennsylva- 

 nia. Also in California and along the coast of South Amer- 

 ica. Widely distributed in the Old World. June-Sept. 



4. L. Salicaria. 



