28 CRUCIFER-E. (mustard FAMILY.) 



2. S. Thaliana, (Jaud. Stom smooth and brauched al)ove, hairy at the 

 basf, G -12' liigli, lowest leaves spatulato-obijvate, petioled, tlio ui)per lance- 

 olate, sessile, 1' long ; petals white, exserted ; silitiues linear, spreading, longer 

 than ])edicel. (C'ardaniinc spatlmlata, Miihx. '.) — Low ground in the ujiper 

 districts. Introdiued. April. [2J. 



3. S. ofl&Cinale, Seop. Stem 2° -a'' high, wideh branched; leaves run- 

 cinate, ]iiilns(tiii ; ])etals yellow; silicjnc subulate, nearly sessile, appressed to 

 the rhachis. — Waste ground in tlie n])per districts. Introduced. (J^. 



9. WAREA, Nutt 



Sili(|uc linear, flattened, long-stalked, recurved ; tiie valves 1-nerved. Seeds 

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

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

 racemes. I'etals long-clawed, white or purple. 



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

 oval, bright purple ; silitjue linear. — Sand hills, Florida. Sept. — Stem \° - 

 2° high. 



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

 white or rarely purple ; siliijue narrow-linear. — Sand hills, Florida and 

 Georgia. Sept. — Stem 1 ° - 2° high. 



10. ERYSIMUM, L. 



Silique linear, 4-angular, the waives keeled. Seeds in a single row in each 

 cell, oblong, marginless. Cotyledon flat, incumbent. — Chiefly biennial herbs, 

 with narrow leaves, aud yellow flowers. 



1. E. cheiranthoides, L. (Wormseed Mustard.) Stem erect, 

 brandling above, clnsely jjuhescent ; leaves thin, lanceolate, acute, entire or 

 slightly toothed, roughish ; flowers small ; silicjue ascending, rather longer 

 than the slender pedicel, the angles rounded. — North Carolina (Curtis). 

 July. — Stem l°-2° high. Silique 8'- 10' long. 



11. HESPERIS, L. KocKET. 



Sili(iue nearly terete. Seeds oblong-tritjuetrous. Cotyledons incumbent, 

 Petals obovate or linear. Stigmas erect. — Chiefly annuals or biennials. 



1. H. matronalis, L. Stem tall, simple, pubescent; leaves ol)long, 

 roughish, denticulate ; petals large purple. — North Carolina. Escaped from 

 cultivation. 



12. SINAPIS, L. Mustard. 



Silique terete or 4-angled, prolonged into an empty or 1 -seeded beak, the 

 valves 1 - 5-nerved. Seed globose, in a single row. Cotyledons incumbent, 

 folded around the radical. — Erect branching annual or biennial herbs, with 

 coarse pinnatifid leaves, and yellow flowers. All introduced. 



1. S. nigra, L. (Black Mustard.) Sili(|ues smooth, appressed to the 

 rachis ; beak short ; seed dark brown. — Grain-fields. 



