Vor,. II.] 



MUSTARD FAMILY. 



119 



3. Brassica arvensis (L,.) B.S.P. 



Charlock. Wild Mustard. 



(Fig. 1703.) 



Sinapts arvensis L,. Sp. PI. 668. 1753. 



Brassica Sinapistrum Boiss. Voy. Espagne, 2: 

 39- 1839-45. 



Brassica arvensis B.S.P. Prel. Cat. N. Y. 1888. 



Erect, i-2 high, hispid with scattered 

 stiff hairs, or glabrate, branching above. 

 Leaves similar to those of B. nigra but gen- 

 erally not so much pinuatifid; flowers 6 // - 

 8" broad; pedicels stout, 2 // ~3 // long in fruit; 

 pods glabrous, spreading or ascending, some- 

 what constricted between the seeds, 6 // -8 // 

 long, i ff wide, tipped with a flattened elon- 

 gated-conic often i-seeded beak 5 // -6 // long, 

 the valves strongly nerved. 



In fields and waste places, frequent or occa- 

 sional. Adventive from Europe and widely dis- 

 tributed as a weed. English names, Corn Mus- 

 tard, Chadlock, Corn- or Field-Kale. May- 

 Nov. 



4. Brassica campestris I,. 



Turnip. Wild Navew. 



(Fig. 1704.) 



Brassica campestris L. Sp. PI. 666. 1753. 



Stem i-3 high, branching, glabrous 

 and glaucous, or sometimes slightly pubes- 

 cent below. Lower leaves petioled, pu- 

 bescent, more or less lobed or pinnatifid; 

 upper leaves lanceolate or oblong, acute 

 or obtusish, sessile and clasping the stein 

 by an auricled base, entire or dentate, 

 glabrous; flowers bright yellow, 4 // -5 // 

 broad; pedicels spreading or ascending, 

 often i' long in fruit; pods \y 2 '-i' long, 

 tipped with a beak 4 // ~5 // long. 



In cultivated grounds, sometimes persist- 

 ing for a year or two, and occasional in waste 

 places eastward. Fugitive from Europe. 

 April-Oct. 



Brassica Napus I,. (RAPE) has all the leaves 

 glabrous, and is sometimes found in waste 

 places. 



13. DIPLOTAXIS DC. Syst. 2: 628. 1821. 



Annual or perennial herbs, similar to the Mustards, with basal and alternate pinnatifid 

 or lobed leaves, and rather large yellow flowers in terminal racemes. Silique elongated, 

 linear, flat or flattish, short-beaked or beakless, the valves mostly i -nerved. Style usually 

 slender. Seeds in 2 complete or incomplete rows in each cavity of the silique, marginless; 

 cotyledons conduplicate. [Greek, referring to the double rows of seeds.] 



About 20 species, natives of the Old World, the following fugitive or adventive in our territory. 

 The genus is often united with Brassica. 



Perennial; stem leafy nearly to the inflorescence. I. D. tenuifolia. 



Annual; leaves mostly basal, oblanceolate. 2. D. muralis. 



