296 Obdee 46.— LBGUMINOS^. 



12 P. ii^na DC. Low, ascending; Iva. obovate and spatulate, mostly radical; 

 heads ovate, becoming oblong, dense; wings lanoe-ovate, cuspidate-acuminate 

 twice longer than tbe slightly crested k^el. — S. States, in pine woods, common. 

 Sts. 3 to 5' high. Lts. 1 to 2' long, rosulate. Head often near 1' thick, dispro- 

 portionately large, the fls. citron-yeUow, changing to green. Apr., May. 



13 "P. ramosa Bll. Erect, corymboualy branched above; spikes loose, oblong, 

 numerous, forming one or more dense, level-topped cymes; radical Ivs. fmu 

 (small), spatulate, cauUna obkmg-linear ; seed oval, carunded. — Swamps, Del. to 

 Pla. andLa. This and the next are species of singular aspect. St. If high. Lvs. 

 about 6'' long, few at the root. Spikes about 4" diam., the fls. greenish yellow, 

 becoming finally dark green. Fls. pedicelled. Jn. — Aug. (P. corymbosa Nutt.) 



14 P. cymdsa "Walt. Sts. tall, simple, corymbously branched at top ; hs. mosUy 

 radical, linear, pointed, crowded; stem lvs. very few, linear-subulate ; racemes 

 spike-like, numerous, forming a dense, faatigiate cyme ; seed globular, naked. — 

 Swamps, in the pine woods, N. Car. to Pla. Sts. often many from the same root, 

 2 to 4 or 5f high. lvs. grass-like, 2 to 3' long, forming a dense tuft at base. 

 Fls. pedicelled, greenish yeUow, becoming finally greenish-brown. Jn. — Aug. 

 (P. attenuata Ell. graminifolia Poir. aoutifolia T. & G.) 



ISP. verticilldta L. St. ranched above, erect ; lvs. linear, verticillate both 

 on the stem and opposite branches ; spikes slender, stalked ; fls. alternate, crested ; 

 calycine wings roundish ; seed oblong, smooth, caruncle hardly half as long. — 

 Found on dry hills, U. S. and Can. St. very slender, square, 6 to 8' high. Lvs. 

 in whorls of 5 or 6, 4 to 10" long, 1" wide. Fls. small, greenish-white, in 

 racemes 3 to 10'' long, which are higher upon the branches than upon the main 

 stem. Jl. — Oct. 

 p. AMEiGtrA. Branches filiform, alternate ; lower lvs. verticillate, upper alter- 

 nate ; spikes elongated, with the fls. scattered ; seed exactly as in a. — Dry 

 fields and woods, Mass. to Tenn. 



16 P. Boykinii Torr. & Gr. Sts. erect from an ascending base, simple ; lvs. 

 obovate and lanceolate ; whorled, a few of the upper linear and alternate ; spike 

 slender, pointed, dense ; wings, roundish, concave ; canmcle § the length of Oie very 

 Jmiry seed. — Ga. and Fla. Sts. slender, several from the same root, 12 to 18' 

 high. Lvs. 6 to 12" long, in 3s, 4s, and 5s. Fls. whitish, the wings green, with 

 white borders. Jn., Aug. 



1'7 P. cruoiata L. St. erect, somewhat fastigiate, winged at the angles ; lvs. 



verticillate in 4s, linear-oblong, punctate, spikes ovate, dense, obtuse, sessile or 



nearly so ; seed ovate, smooth, caruncle fiMy as long ; wings delioid-ovate, cuspidate. 



— In sphagnous swamps and other low grounds, Mass. to Fla. and La. St. 3 to 12' 



high, very slender, smooth, slightly winged at the 4 angles. Lvs. 2 to 10" or 



more long, 1 to 2" wide (upper ones largest), obtuse, tapering to the base, with 



small, resinous dots. Spikes capitate, 5" thick. Wings greenish-purple, much 



dilated at base. Jl., Aug. 



(8. OUSPIDATA. Lvs. linear ; heads larger, oblong, squarrous with the elongated 



cusps of the wings. This is the more common southern form. (P. cuspidata 



Hook.) 



18 P. brevifdlia Nutt. Slender, branched above ; lvs. linear, short, remote, in 

 4a, or on the branches scattered; spike oblong, dense, obtuse, on long peduncles; 

 wings ovate-lanceolate, acute; seed just as in No. 1'7. — N. T. to Fla. About It 

 high. Heads 4" thick, 1 to 2' long (as appears from the squarrous rachis). Lvs. 

 6 to 9" long. Fls. roseate. Aug., Sept. 

 P. Baldwinii Nutt of S. E. Georgia is unknown to the author, unless it be a 



-variety of P. ramosa, differing in its more dense heads of greenish-white fiowers. 



Okder XLVI. LEGTJMINOS^. Leguminous Plants. 



Eerbs, shrubs, or trees. Leaves alternate, usually compound, mar^s entire. 

 Stipuies 2, at the tumid base of the petiole. Stipels commonly 2, Sepals 5, more 

 or less united, often unequal, the odd one always anterior. Petals 5, cither papilio- 

 naceous or regular, perigynous, the odd one (when present) posterior. Stamens 



