\ 



LV. O.NAGRACEiE. 261 



5. L. viRGATUM. Austrian Dythrum. — >S^. 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 — 4rf high. Flowers purple. Jn. — Sept. f 



3. DECODON. Gmel. 



Gr. ScKa, ten, o6ovs, a tooth; from the horn-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. — >S^. and lvs. beneath pubescent. R. Island. 



0. IcEvigatum. — Glabrous and bright green. Most common in N, Eng. 



4. CUPHEA. 



Gr. Kvcpog, 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 svffruticose. Lvs. opposite^ entire, 

 Fls. axillary and terminal. 



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

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

 fis. on short peduncles; col. gibbous at base on the upper side, 12-veined, 

 6-toothed, very viscid. — (T) 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, I 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., minute. 

 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. 



P7anrs herbaceous, sometimes shrubby, with alternate or opposite leaves. 

 Fla. axillary, or in terminal spikes or racemes. 



Ca/.— Sepals 4, (2—6) united below into a tube, the lobes valvate in oestivation. 



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.— \ trinneular, often cohering by threads. 

 Ova. coherent with ilie tube of ttio caly.x ; placenta in the axis. 

 Ft. 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 



