CRUCIFERACEAE (MUSTARD FAMILY) 113 



RORIPA (Cress) 



Leaves simple to pinnately compound, rarely entire. .Flowers white or 

 yellow. Sepals greenish yellow. Petals short-clawed. Stamens 1-6. 

 Stigma entire to 2-lobed. Pod terete or nearly so, not stipitate. Seeds 

 minute, turgid, wingless, in 2 rows in each cell. — (Said to be from Celtic 

 ros = dew, ripa = a bank; referring to the habitat of some species.) 



A. Flowers white; leaves either pinnately divided or else very large. 



B. Leaves all pinnate; basal leaves 7.S-1S cm. long; pod linear; roots with mild 

 radish taste. W. E. — ■ Edible. R. nasturtium (water cress) 



BB. Rarely some of the lower leaves pinnate; basal leaves 45 cm. or less long; pod 

 globular; roots with extremely strong radish taste. W. E. — Ground roots com- 

 monly eaten as a condiment. R. armorica (horse-radish) 

 AA. Flowers yellow; leaves various, mostly pinnate, not extremely large. 



C. Perennial by running rhizomes; stems diffuse. E. 



R. sinuata (spreading yellow cress) 

 CC. Annual or biennial, without rhizomes. 

 D. Stems diffuse, branched from the base; pedicels 6-8 mm. long. 



E. Stem hispid; pod 3-5 mm. long. E. R. hispida (hairy cress) 

 EE. Stem glabrous throughout or nearly so; pod 2-12 mm. long. W. E. 



R. palustiis (marsh cress) 

 DD. Stems erect, simple below; pedicels 2-4 mm. long, 



F. Pod curved; leaf lobes acute. W. E. R. currisiliqua (arc cress) 

 FF. Pod straight or nearly so; leaf lobes obtuse. E. R. obtusa (blunt cress) 



CARDAMINE (Bitter Cress) 



Annual or perennial. Leaves entire to pinnately compound. Flowers 

 white or purple, in racemes or corymbs. Petals obovate to narrowly spat- 

 ulate. Stamens 4 or 6. Pod linear, not stipitate. Seeds in i row in each 

 cell, flat, marginless. — (Gk. kardia = the heartj damao = to strengthen ; 

 from the cordial properties of some.) 



A. Leaves all simple. 



B. Leaves ovate to elliptic, entire; alpine, C. 



C. bellidifolia (alpine bitter cress) 

 BB. Leaves cordate to reniform, sinuate to toothed; subalpine. C. E. 



C. cordifolia (mountain bitter cress) 

 \A. Leaves or some of them pinnately compound. 



C. Basal leaves simple; stem-leaves 3-s-foliolate. W. C. E. 



C. breweri (brewer's bitter cress) 

 CC. Basal leaves pinnately compound. 

 D. Leaves all 3-foliolate or sometimes 5-foliolate; leaflets coarsely 3-5-toothed. 

 W. C. C. angulata (3-leaved bitter cress) 



DD. Leaves 3-1 3-foliolate, only the smaller leaves if any 3-5-foliolate; leaflets 

 coarsely toothed in some species. 

 E. Leaves 7-13-foliolate; leaflets of basal leaves orbicular. W. E. 



C. pratensis (cuckoo flower) 

 EE. Leaves 3-7-foliolate. 

 F. Flowers 2-3 mm. wide; leaflets petiolulate, lateral ones oblong. W. C. E. 



C. parviflora (small bitter cress) 

 FF. Flowers 4-8 mm. wide. 



r, & R. EL. FL. — 8 



