96 FOUNDATIONS OF BOTANY 
2. B. juncea, Coss. Similar to the preceding, but nearly or quite 
smooth. Pedicels slender. Beak of the cylindric pod slender, 
conical, not containing a seed. Recently introduced from Asia and 
becoming very abundant eastward. 
3. B. alba, Boiss) Wuitre Mustarp. Stem 2-5 ft. high, with 
reflexed hairs. Upper leaves pinnately cut. Pods borne on spread- 
ing pedicels, bristly, with a sword-shaped, 1-seeded beak occupying 
more than half their length. Seeds pale. Cultivated from Europe 
and introduced to some extent. 
4. B. nigra, Koch. Brack Mustarp. Stem 3-6 ft. high, some- 
what hairy. Lower leaves lyrate with the terminal lobe much the 
longest, stem-leaves linear-lanceolate, entire or toothed, smooth. 
Pods awl-shaped, 4-angled, smooth, lying against the stem. Seeds _ 
brownish, more biting than in No. 2. Cultivated from Europe and 
introduced. 
x V. RAPHANUS, Tourn. 
Annual or biennial herbs. Root-leaves lyrate. Flowers in 
long racemes, white or yellow, purple-veined. Sepals erect. 
Pods rather long, slender-beaked, not splitting open but some- 
times breaking across into 1-seeded joints. 
1. R. Raphanistrum, L. Witp Rapisn, JoInNTED CHARLOCK. 
A stout, hairy annual 1-2 ft. high. Leaves cut into remote seg- 
ments, which are coarsely toothed or serrate; terminal segment 
largest. Flowers yellow, turning whitish or purplish. Pods 
necklace-shaped, with a long beak. A common weed eastward, 
introduced from Europe. 
VI. NASTURTIUM, R. Br. 
Annual or biennial, mostly aquatic plants. Stems erect or 
diffuse, often widely branching. Leaves simple, pinnately 
lobed. Flowers small, white or yellow. Sepals spreading. 
Stamens 1-6. Pod short and broad or nearly linear. Seeds 
numerous in 2 rows in each cell.* 
1. N. officinale, R. Br. WaAtTrerRcREss. Aquatic herbs. Stems 
smooth, diffuse, rooting at the joints. Leaves with 3-9 rounded, 
pinnate lobes, the terminal lobe much the largest. Racemes 
elongating in fruit. Petals white, twice the length of the sepals. 
Pods linear, 3-2 in. long, on slender, spreading pedicels. In ditches 
and slow streams. Often used for salad.* 
2. N. palustre, DC. YreLttow Warercress. Annual or bien- 
nial. Stem erect, branched, slightly downy. Leaves irregularly 
