28 CRUCIFKU.K. (mISTAUI) I AMII-Y.) 



5. A. Canadensis, T^. Stem stout, simple, nenrly smonth nl>ovc ; leaves 

 thin, downy, huicoolate, slightly tootlied, sessile \>y a narrow ha.sc, the lowest 

 coarsely or pinnatifid-toothod ; sili(|uos eun'cd, droo])inf;, on rouyh pedicels; 

 seeds winj:ed. (A. falcnta, Mic/ix.) — Dry or roeky plaees in tlie upper districts. 

 May and June. — Stems 2° -3° liijih. Silique 2' -3' long. Flowei-s white. 

 Petals ohlon<ij-linear, not twice the length of the hairy calyx. 



6. A. laevigata, DC. Smooth and glaucous ; stem erect ; leaves linear 

 or lanceolate, entire or sparingly toothed, sagittate and cla.sping at the base ; 

 pedicels short; petals (wliitisli) narrow, slightly exsertcd ; silique elongated, 

 narrow-linear, recurved-spreading ; seed winged. — Koeky j)laces, North Caro- 

 lina, Tennessee, and nurtliwanl. May. — Stem l°-2° high. Silicjuc 2'-3' 

 long. 



7. SISYMBRIUM, L. HicnGE-MrsTARn. 



Silique linear or oblong, terete or somewhat angled, with 1 -3-nervcd valves. 

 Seeds in a single row in eadi cell, ohlong, marginloss. Cotyledons linear-oblong, 

 incuml)ent. — Herbs with simple or pinnately divided leaves. Flowers in ra- 

 cemcs, small, white or yellow. 



1. S. canescens, Nutt. Pubescent and somewhat hoary ; stem simple or 

 sparingly hranc'lied ; leaves bipinnatifid, with small mostly toothed lobes ; ra- 

 cemes at length elongated ; silique shorter than the spreading pe<licel. (Carda- 

 mine ? multifida, DC.) — Waste ground, Florida, northward and westward. 

 March and April. (^ — Stem l°-2° high. Flowers small, greenish-white. 



2. S. Thaliana, Gaud. Stem slender, branching, hairy at the base ; leaves 

 hairy, tootlied or entire, the lowest obovate or oblanceolate, tufted, the others 

 small and scattered ; siliques linear, erect-spreading, twice as long as the pedi- 

 cels. — Rocks and sterile soil, Georgia and northward. Introduced. March 

 and April, (f — Stem 4' -8' high. Flowers white. 



3. S. oflQ-Cinale, Scop. Stem tall (2° -.3°), branching, and with the nin- 

 cinate leaves pubescent; silique subulate, nearly sessile, appressed to the rachis. 

 — Waste grounds in the upper districts, and northward. Introduced. May - 

 Sept. (X — Flowers pale yellow. 



8. WAREA, Nutt. 



Silique linear, flattened, long-stalked, recun-ed ; the valves l-ner>-ed. Seeds 

 in a single row in each cell. Cotyledons oblong, flat, incumbent. — Smooth 

 and erect branching annuals. Leaves entire. Flowers showy, in corymb-like 

 racemes. Petals long-clawed, white or purple. 



1. W. amplexifolia, Nutt. Leaves oval and slightly clasping; petals 

 oval, bright-purple ; silique linear. — Sand hills, Florida. September. — Stem 

 lo-2° high. 



2. W. cuneifolia, Nutt. Leaves wedge-lanceolate ; petals obovate, white 

 or rarely purple; silique narrow-linear. — Sand hills, Florida and Georgia. 

 September. — Stem 1° - 2° high. 



