:5-2 CRUCIPER&. [DRABA. 



1. D. aizoi des, L. ; leaves rigid ciliate, scape leafless, petals yellow. 

 Walls and rocks, Pennard Castle and Worm's Head, Glamorgan ; a native ? 



WaJtaon ; fl. March-May. Perennial, densely tufted. Leaves ^ in., rosulate, 

 glabrous, shining, keeled, with white cartilaginous ciliate margins and tip. 

 Scape 1-5 in., rigid. Raceme short, slightly lengthened after flowering. Flowers 

 J in. diam. Petals hardly notched. Pod oblong, acute, glabrous ; style 

 half its length; cells 10-12-seeded. DISTRIB. Sub-Alpine, Central and S. 

 Europe, W. Asia. 



2. D. rupes'tris, Br. erect, small, leaves oblong-lanceolate hairy, 

 scape-leaf 1 or 0, petals white, pod small straight oblong hairy, pedicel 

 straight erecto-patent. 



Alpine rocks, alt. 3-4,000 ft., rare and local ; Ben Lawers, Cairngorm, Ben- 

 hope ; fl. July- Aug. Roolstock slender. Leaves |-^ in., ciliate, rarely 

 toothed. Scapes one or more, 1-2 in., slender, flexuous ; their leaf sessile, 

 stellately pubescent. Flowers | in. diam., few, white. Pod in., oblong, 

 obtuse ; stigma subsessile. DISTRIB. Arctic Europe, Siberia, Arctic 

 America. The Ingleborough plant, gathered by Sir Wm. Hooker, 

 and referred to by Syme (Engl. Bot. 1. 103), is a small state of D. 

 incana. 



3. D. inca'na, L. ; erect, stellately hispid, often branched, leaves oblong 

 anline amplexicaul, petals white, pod linear or oblong-lanceolate usually 

 twisted, pedicel erecto-patent. D. confu'sa, Ehrh. 



Alpine rocks, England, Wales, Scotland, ascending above 3,000 ft., mountains 

 and maritime sandhills of S.W. Ireland ; fl. June-July. Rootstock often 

 woody and long. Stem 6-14 in. Radical leaves short, ^-1 in., densely 

 rosulate, usually much toothed ; cauline many, suberect. Racemes much 

 elongated after flowering, many-flowered. Flowers as in D. ruuestris. Pods 

 {-% in., variable in length breadth and twisting, glabrous or hairy, obtuse 

 or subacute ; stigma subsessile ; pedicels short ; seeds many. DISTRIB. N. 

 Europe (Arctic), Alps, N. Asia to the Himalaya ; Alpine and Arctic America. 

 Very variable ; small, unbranched specimens with few stem-leaves re- 

 semble D. rupestris. 



4. D. mura'lis, L. ; suberect or prostrate, stellate-hispid, slender, 

 branched, stem-leaves broadly ovate or cordate obtuse coarsely toothed, 

 petals minute white, pods linear-oblong horizontal, pedicels spreading. 

 Limestone rocks and walls in W. England from Westmoreland (ascending to 



1,200 ft. in Yorkshire) to Somerset, introd. in Scotland and N. W. Ireland ; 

 fl. April-May. Rootstock annual or biennial, slender. Stem 1-2 ft., flexuous. 

 Radical leaves small, j-1 in., obovate ; cauline few, distant, broader. Flowers 

 J in. diam. Raceme short, fruiting long. Pods in., flat, obtuse, on pedi- 

 cels longer than themselves; style ; seeds 10-12, minute. DISTRIB. Europe, 

 temp. Asia to the Himalaya, N. Africa. 



12. EROPH'liiA, DC. VERNAL WHITLOW-GRASS. 

 Small annual or biennial herbs. Radical leaves entire, spreading. Scapes 

 slender, leafless. Flowers few, small, white. Sepals spreading, equal at the 

 base. Petals obovate, 2-lobed or 2-partite. Pod oblong, compressed ; valves 

 1 -nerved, membranous, flat or convex ; septum membranous. Seeds 2-seri- 

 ate, very many and minute ; funicle capillary ; cotyledons accumbent. 



