LV. ONAGRACEiE. 261 



5. L. viRGATUM. Aust/rian L/ythrum. — St. erect, branched, virgate ; Ivs. lan- 

 ceolate, acute at each end, floral ones small ; fls. about 3 in each axil of the vir- 

 gate raceme ; sta. 12. — A fine species for the garden, native of Austria. Stem 

 3 — 4f high. Flowers purple. Jn. — Sept. f 



3. DEC DON, Gmel. 



Gr. SeKa, ten, oSovs, a tooth; from the hom-like teeth of the calyx. 



Calyx short, broadly campanulate, with 5 erect teeth, and 5 elon- 

 gated, spreading, horn-like processes ; stamens 10, alternate ones very 

 long ; style filiform ; capsule globose, included, many-seeded. — %■ Lvs. 



opposite or verticillate, entire. Fls. axillary., purple. 



D. vERTiciLLATUM. Ell. (Lythrum. Linn. Nessea. Kunth.') 

 Swamps throughout the U. S. and Can. Stem woody at base, often pros- 

 trate, and rooting at the summit, 3 — 8f in length, or erect and 2 — 3f high, 4 — 6 

 angled. Leaves opposite or in whorls of 3, lanceolate, on short petioles, acute 

 at base, 3 — 5' long, gradually acuminate and acute at apex. Flowers in axil- 

 lary, subsessile umbels of 3 or more, apparently whorled, constituting a long, 

 leafy, terminal and showy panicle. Petals 5 or 6, large, and of a fine purple. 

 Jl. Aug. 



a. pubescens. — St. and lvs. beneath pubescent. R. Island. 



p. leevigatum. — Glabrous and bright green. Most common in N. Eng. 



4. CUPHEA. 



Gr. Kvipos, curved or gibbous ; in reference to the capsule. 



Calyx tubular, ventricose, with 6 erect teeth, and often as many 

 intermediate processes; petals 6 — 7, unequal; stamens 11 — 14, 

 rarely 6 — 7, unequal ; style filiform ; capsule membranaceous, 1 — 2- 

 celled, few-seeded. — Herbaceous or suffruticose. Lvs. opposite, entire. 

 Fls. axillary and terminal. 



C. viscosissiMA. Jacq. (Lythrum petiolatum. Linn.) 

 Herbaceous, viscid-pubescent ; lvs. ovate-lanceolate, petiolate, scabrous ; 

 fls. on short peduncles; cal. gibbous at base on the upper side, 13-veined, 

 6-toothed, very viscid. — ® Wet grounds, Pittsfield, Mass., Hitchcock, Cam- 

 bridge, N. Y., Stevenson, to Ga. and Ark. Stem 9 — 18' high, with alternate 

 branches. Leaves somewhat repand, 1 — 2' long, ^ as wide, on petioles \ as 

 long. Flowers solitary, one in each axil, irregular. Calyx often purple, ven- 

 tricose. Petals violet, obovate. Stamens included. Capsule bursting length- 

 wise before the seeds are ripe. Aug. 



5. HYPOBRICHIA. Curtis. 

 Calyx 4-lobed, without accessory teeth ; petals ; stamens 2 — 4 ; 

 ovary 2-celled ; stigma 2-lobed, subsessile ; capsule globose, bursting 

 irregularly, many-seeded. — A submersed aquatic herb. Lvs. opposite, 

 crowded, linear. Fls. axillary, sessile, miyiute. 

 H. NuTTALLTi. Curt. (Peplis diandra. Nutt.) 



A little inhabitant of ponds and sluggish streams, 111., Mead, Buckley, to 

 Mo. and La. Its habit is similar to a Callitriche. Stem mostly submersed, 

 10 — 20' long. Leaves 10 — 15" by 1 — 2", very numerous. Jn. — Aug. 



Order LV. ONAGRACE^.— Onagrads. 



Plants herbaceous, sometimes shrubby, with alternate or opposite leaves. 

 Tls. axillary, or in terminal spikes or racemes. 



Ca?.— Sepals 4, (2—6) united below into a tube, the lobes valvate in [estivation. 



Cor.— i Petals 4, (2—6) inserted with the 4 or 8 (1—2—3—8) stamens into the throat of the calyx. Pollen 

 Sta. — I triangular, often cohering by threads. 

 Ova. coherent with the tube of the calyx ; placenta in the axis. 

 Fr. baccate or capsular, 2—4 celled, many-seeded. Albumen none. 

 Genera 36, species 520, particularly abundant throughout America, more rare in the Old World. They 



