CRUCIFERAE (MUSTARD FAMILY) 215 



nerved valves. Seeds oblong, in 1 row. An important genus, giving us the 

 cabbage, turnip, mustard, etc.; when running wild becoming unsightly weeds. 



Siliques spreading, gradually beaked 1. B. arvensis. 



Siliques appressed, abruptly beaked . . . . . . . . 2. B. nigra. 



1. Brassica arvensis (L.) B. S. P. Prel. Cat. N. Y. 1888. Rough with scat- 

 tered hairs, 3-5 dm. high: lower leaves pinnatifid, long-petioled, the terminal 

 lobe large and toothed; upper smaller and sometimes nearly entire: ped- 

 icels stout, short: silique sessile, spreading, tapering to the flattened beak 

 which is often 1-seeded. CHARLOCK, WILD MUSTARD. Introduced, and more 

 or less common as a weed. 



2. Brassica nigra (L.) Koch, in Roehl, Deutsche Fl. Ed. 3. 4: 713. 1833. 

 Very similar but usually larger: the leaves more pinnatifid, the uppermost 

 reduced to oblong-lanceolate entire sessile blades: silique cylindric or 4-sided, 

 abruptly contracted to the short beak, closely appressed to the rachis. BLACK 

 MUSTARD. Infrequent; in waste places. 



10. RAPHANUS L. WILD RADISH 



Erect biennial herbs with pinnate or lyrate leaves and large showy flowers 

 in panicled racemes. Sepals oblong, the lateral somewhat saccate. Petals 

 large, long-clawed, yellow or fading to white. Siliques linear-conical, cori- 

 aceous, indehiscent, constricted between the seeds or continuous or spongy 

 within, tipped by the slender style. Seeds subglobose. 



1. Raphanus raphanisrrum L. Sp. PI. 669. 1753. Stem erect and freely 

 branching, 4-7 dm. high, hispid pubescent below: the lower leaves lyrate- 

 pinnatifid; the upper reduced, becoming oblong and entire: siliques 3-4 cm. 

 long. WILD RADISH. An occasional weed in waste places. 



11. BARBAREA R. Br. WINTER CRESS 



An erect branching biennial, with angled stem, lyrately pinnatifid leaves, 

 and yellowish racemose flowers. Silique linear, somewhat 4-angled, pointed. 

 Seeds in 1 row in each cell. 



1. Barbarea americana Rydb. Mem. N. Y. Bot. Card. 1: 174. 1900. Gla- 

 brous erect biennial 2-4 dm. high: basal leaves broadly elliptic, wavy, simple, 

 or with 1 or 2 pairs of small lobes on the petiole; lower stem leaves similar 

 but with the petiole clasping at base ; upper stem leaves sinuately toothed or 

 lobed: petals spatulate, about 3 mm. long: silique somewhat 4-angled, 2-3 cm. 

 long, pointed with the short style, suberect, on short spreading pedicels. 

 This native species was long mistaken for the European B. vulgaris, natural- 

 ized in many parts of the United States. 



12. RORIPA Scop. CRESS 



Mostly glabrous biennials or perennials, with simple or pinnately lobed or 

 lyrate leaves and yellow or white flowers. Sepals flat, nearly equal at base. 

 Petals short-clawed. Silique sessile, usually short, subterete; style short and 

 rather thick; valves 1-nerved. Seeds in 2 rows, turgid. Plants growing 

 mostly in wet places, or rarely in the water. Nasturtium. 



Flowers white; aquatic perennial 1. R. Nasturtium. 



Flowers yellow. 



Perennial by running rootstocks 2. R. sinuata. 



Annual or biennial. 



Stems erect, simple below, 2-10 dm. high. 



Hispidly hirsute on stems ....... 3. R. hispida. 



Glabrous throughout (or nearly so) . . . . . . 4. R. palustris. 



Stems branched from the base, low and spreading. 

 Fruiting raceme normal. 



Silique slender, curved, 8-1 5 mm. long 5. R. curvisiliqua. 



Silique short, straight, 5-7 mm. long 6. R. lyrata. 



Fruiting raceme unilateral 7. R. curvipes. 



