MUSTARD FAMILY. 217 



yellowish, ascending; petals with elliptic hlade; pods terete, 1^ to IJ 

 in. long, narrowed into a subulate beak, tipped with a flat stigma. 



Very common. Feb.-Apr. It is the Turnip of the gardens run 

 wild. 



2. B. arvensis (L.) B. S. P. Charlock. Herbage light green, 

 hispid with scattered hairs; leaves pinnatifld with a lai-ge shallowly 

 lobed terminal segment and usually » pair of much smaller angular 

 segments on the rachis, or ovate or triangular-ovate and lohed or 

 denticulate; upper leaves deltoid-ovate to ovate-lanceolate, petioled 

 or sessile by a narrow base, not clasping; petals 4 to 6 lines long; pods 

 ascending or erect, 1 to 1 J in. long, with 3 to 8 seeds in each ceil; beak 

 flattish, J as long as the body, often containing a seed; valves nerved. 

 — (B. Sinapistrum Boiss.) 



Frequent in western Alameda Co. Apr. 



3. B. nigra (L.I Koch. Black 3[ustakd. Dark green (not 

 glaucous), nearly glabrous or with some .scattered stiff hairs, 3 to 6 

 or even 12 ft. high; leaves all petiolate; lower lyrately pinnatifld or 

 divided; terminal segment very large, shallowly lobed and sharply 

 dentate; upper leaves less lobed or the uppermost linear and entire 

 and commonly drooping or pendulous; racemes long and dense; 

 petals 3J lines long, much larger than the sepals; pods closely 

 appressed to the axis of the raceme, torulose, indistinctlj- 4-sided, 

 beaked by the style; seeds nearly black, highly pungent. 



Naturalized weed, everywhere common and very abundant in 

 interior grainfields. May-July. 



4. B. alba Boiss. Stem 1 to 2 ft. high; leaves all pinnately lobed 

 or divided and rather long-petioled, or the upper lanceolate or oblong, 

 merely dentate and short-petioled; racemes 8 or 4 in. long, rather 

 dense; pedicels in fruit spreading horizontally; pod hispid with white 

 hairs, the body shorter than the long conspicuously flattened beak. 



European weed, perhaps not yet naturalized: Byron, Biol-etti. 



6. RAPHANUS L. Radish. 

 Coarse much-branched annuals or biennials. Lower leaves lyrately 

 pinnate or pinnatifld, shortly petioled. Flowers large, purple or 

 yellow, or becoming white. Petals long-clawed. Pod thick, beaked 

 by the stout style, 1-celled, fllled with spongy or corky tissue, lighth- 

 constricted between the seeds or even moniliform, indehiscent or 

 eventually breaking transversely into 1-seeded joints. Seeds sub- 

 globose, cotyledons conduplicate. (Greek raphanos, quick-appearing, 

 on account of the prompt germination of the seeds.) 



Flowers purple, pink or white; pod with shallow constrictions, 2 to 



3-see<ied 1. R. sativus. 



Flowers yellow or white; pod moniliform, 4 to lO-seeded.2. R. Rapkaiiistrum. 



1. R. sativus L. Wild Radish. Nearly glabrous or hispid with 

 scattered hairs; stem branching widely, 2 to 5 ft. high; lower leaves 

 pinnately parted, all the segments crenate, the terminal segment 

 large and round, the lateral smaller, ovate or oblong, sessile with the 



