30 CRUciFER^. [Nasturtmm. 



W. Med.—Oa the walls of Carisbrooke castle in plenty. Frequent on walls 

 and roofs at Yamiouth, as at the caslle, &c. 



Root whitish, tapering, with several lonfj, rigid, nearly simple, slender branches, 

 and havivig the hot pungent smell and taste of horseradish. Stem shrubby, erect 

 or ascending, from 6 to 18 inches high, with a rough, greenish ash-coloured bark, 

 round and in the older plants much branched from the base, forming tufts, the 

 flowering shoots angular and downy. Leaves numerous, scattered and crowded 

 on the young barren and flowering shoots, erect, narrow-lanceolate, very acute, 

 usually quite entire or at most with one or two small teeth (Mertem Sr Koch), firm 

 and persistent in our ordinary winters, tapering into short petioles, their tips a lit- 

 tle recurved, with the strong midrib of the leaf continued into a pale stilfish point ; 

 covered on both sides but most thickly on the under with fine, close-pressed, cen- 

 trally affixed hairs precisely like those of Cornus. Flowers in terminal, corym- 

 bose, simple clusters, of a rich golden- verging upon orange-yellow, very fragrant, 

 on erect or patent quadrangular pedicels about their own length. Calyx purplish 

 brown, the sepals erect, linear-oblong, obtuse, with yellow membranous edges, as 

 long as or longer than the claws of the petals, 2 alternately broader, gibbous at 

 the base and plane at the back, the remaining 2 narrower and strongly keeled, all 

 more or less sprinkled with medifixed hairs. Petals much exceeding the calyx, 

 obovate, spreading, hut not flaccid nor blotched with dark brownish red as in the 

 cultivated Wallflower, somewhat wavy and minutely notched along their margins, 

 with long, narrow, pale claws. Stamens equal in levigth or very nearly so, erect, 

 4 of them opposite the smaller sepals, closely approximated in pairs, unaccompa- 

 nied by hypogynous glands, the 2 solitary stamens surrounded by a dark green 

 4-lobed gland; filaments angular, not compressed nor dilated below; anthers 

 linear oblong, greenish yellow. Style very short ; stigma bilobate, the lobes 

 roundish, at length spreading. >SiKy«es linear, erect, \\ — 2 inches long, acutely 

 2-edged and compressed, with a very short beak and tipped with the stigma, gray- 

 ish with close-pressed medifixed hairs, each valve with a narrow acute dorsal keel. 

 Seeds numerous in each cell, brownish yellow, rugose, in a single row from either 

 edge of the dissepiment, ovate or suborbicular, much compressed, with a broad 

 membranous margin most prominent at the lower end. Cotyledons aocumbent, 

 flat, the radicle curved upwards towards the funiculus. 



III. Nasturtium, R. Br. Cress. 



" Pod nearly cylindrical (sometimes short) ; valves concave, nei- 

 ther nerved nor keeled. Seeds in a double row. Calyx patent." 

 —Br. Fl. 



f Petals white. 



1. N. officinale, R. Br. Common Water-cress. " Leaves pia- 

 nate, leaflets ovate subcordate sinuato-dentate, petals (white) twice 

 as long as the calyx, pods linear." — Br. Fl. p. 27. Sisymbrium 

 Nasturtium, L. : E. B. t. 855. 



In wet ditches, about spring-heads and on the plashy margin of brooks, ponds 

 and rivers, abundantly. Fl. May — October, or even later. If. 



■ff Petals yellow. 



S. N. terrestre, R. Br. Marsh Cress. Annual Yellow Cress. 

 " Leaves Ijrrato-puinatifid unequally toothed, root simply fibrous, 

 petals not longer than the calyx, pods oblong turgid and the sep- 

 tum 2 — 4 times longer than broad." — Br. Fl. p. g8. N. palustre, 

 DC. Sisymbrium terrestre, E. B. t. 1747. 



