u8 



CRUCIFERAE. 



[Voi,. II. 



12. BRASSICA L. Sp. PI. 666. 1753. 



Erect branching annual biennial or perennial herbs, with pinnatifid basal leaves, those 

 of the stem dentate or often nearly entire, and showy yellow flowers in elongated racemes. 

 Siliques elongated, sessile, terete or 4-sided, tipped with an indehiscent conic usually i- 

 seeded beak. Valves convex, i-3-nerved. Stigma truncate or 2-lobed. Seeds in i row in 

 each cell, oblong, marginless; cotyledons conduplicate. [Latin name of the Cabbage.] 



A genus of about 80 species, natives of Europe, Asia and northern Africa. 



None of the leaves clasping the stem, the upper sessile. 



Pods slender, J'-i' long, appressed. i. B. nigra. 



Pods rather slender, i'-z' long, erect, not appressed, on slender pedicels 3" -5" long. 



2. B. juncea. 



Pods spreading or ascending at maturity, on stout pedicels 2" -3," long. 3. B. ~Sinaf>istrum. 

 Upper leaves clasping by an auricled base. 4. B. campestris. 



i. Brassica nigra (L/.) Koch. Black Mustard. (Fig. 1701.) 



Sinapis nigra I,. Sp. PI. 668. 1753. 



Brassica nigra Koch, in Roehl, Deutsche 

 Fl. Ed. 3, 4: 713. 18.33. 



Erect, 2-7 high, freely and widely 

 branching, pubescent or glabrate. Lower 

 leaves slender-petioled, deeply pinnatifid, 

 with i terminal large lobe and 2-4 smaller 

 lateral ones, dentate all around; upper 

 leaves shorter-petiolcd or sessile, pinnati- 

 fid or dentate, the uppermost reduced to 

 lanceolate or oblong entire blades; flowers 

 bright yellow, 3 // -5 // broad; pedicels slen- 

 der, appressed, 2 // long in fruit; pods nar- 

 rowly linear, 4-sided, S"-?" long, %" 

 wide, appressed against the stems and 

 forming very narrow racemes; beak slen- 

 der, i // -2 // long; seeds dark brown. 



In fields and \\asU- places, common 

 throughout our area. Naturalized from Ku 

 rope. Native also of central Asia. June-Nov. 



2. Brassica juncea (L.) Cosson. 

 Indian Mustard. (Fig. 1702.) 



Sinapis juncea L,. Sp. PI. 668. 1753. 



Brassica juncea Cosson, Bull. Soc. Bot. France, 

 6: 609. 1859. 



Annual, pale, glabrous, or slightly pubescent, 

 somewhat glaucous, stem erect, usually stout, 

 i-4 tall. Lower leaves runcinate-piunatifid 

 and dentate, long-petioled, 4 / -6' long, the 

 uppermost sessile or nearly so, lanceolate or 

 linear, commonly entire, much smaller; flow- 

 ers 6"-9 // wide; fruiting racemes sometimes 

 i long; pods erect or nearly so, on slender 

 ascending pedicels $"-5" long, not appressed 

 to the axis, i / -2 / long, rather more than \" 

 wide, the conic-subulate empty beak one- 

 fourth to one-third the length of the body. 



In waste places, New Hampshire and Penn- 

 sylvania to Michigan and Virginia. Adventive 

 or naturalized from Asia. Also introduced into 

 the West Indies and South America. May-July. 



