28 THE CRUCIFER FAMILY. [Nasturtium. 



sometimes scrambling on wet banks or bushes to the length of 2 feet 

 or more. Leaves pinnate, with distant segments, the terminal one 

 usually longer, ovate or orbicular. Flowers small and white, in short 

 racemes. Pod about 6 or 8 lines long or rather more, on spreading 

 pedicels, but slightly curved upwards, the double rows of the seeds 

 very distinct. 



Along brooks and rivulets, throughout Europe and Russian Asia, 

 except the extreme north, naturalised in America and the Colonies. 

 Abundant in Britain except in the Highlands. Fl. the whole summer. 



2. N. sylvestre, Br. (fig. 53). Creeping W. Stem creeping at the 

 base, the flowering branches erect or ascending, a foot high or more. 

 Leaves all or most of them deeply pinnatifid or almost pinnate, the 

 lower lobes distinct and narrow, the terminal one often larger and 

 broader. Flowers yellow and small, although the petals are consider- 

 ably longer than the calyx. Pod nearly that of N. officinale, but rather 

 more slender, and the two rows of seeds rather less distinct. 



On river-banks and in wet places, distributed over Europe and 

 Russian Asia, but apparently not so far north as N. officinale. Spar- 

 ingly scattered over England and Ireland, and still more rare in 

 Scotland. Fl. summer. 



3. N. palustre, DC. (fig. 54). Marsh W. Much resembles N. 

 sylvestre, but usually weaker and not so tall, the lobes of the leaves 

 rather broader and more toothed, the petals seldom exceed the calyx, 

 and the pod is seldom above 3 lines long, slightly curved, the seeds 

 much crowded, in 2 distinct rows in each cell. N. terrestre, Sm. 



In muddy and watery places, throughout Europe and Russian Asia, 

 from the Mediterranean to the Arctic regions, in North America, and in 

 Australia. Pretty frequent in England and Ireland, but decreasing 

 considerably in Scotland. FL summer and winter. 



4. N. amphibium, Br. (fig. 55). Great W. A taller and more 

 erect plant than any of the preceding, attaining 2 or 8 feet. Leaves 

 less divided, sometimes narrow lanceolate 3 or 4 inches long, and only 

 slightly toothed, more frequently deeply toothed or pinnately lobed, 

 sometimes divided to the midrib into narrow segments. Flowers 

 yellow, larger than in the two last, the petals longer than the calyx. 

 Pod straight, elliptical, about 2 lines long, or sometimes shorter and 

 almost globular, the style much longer than in the other species. 



In moist meadows and watery places, throughout Europe and 

 Russian Asia. Generally distributed over England and Ireland, but 

 not very common. Fl. summer. The shortness of the pod in this and 

 in some varieties of N. palustre has induced some botanists to remove 

 them to the genus Armoracia (the Horse-radish), a junction which is 

 purely artificial. 



V. ARABIS. ROCKCRESS. 



Annuals or perennials, usually erect and hairy, at least at their base, 

 with a spreading tuft of radical leaves, which are occasionally lobed, 

 the stem-leaves undivided, sessile or stem-clasping ; the flowers white, 

 or, in a few exotic species, purple. Pod long and linear, the stigma 

 pearly sessile, the valves flat or slightly convex, often with a distinct 

 midrib or several longitudinal veins. Seeds more or less flattened, 

 often winged^ Radiple accurnbent, rarely obliquely incumbent. 



