CRUCIFERiE. 43 



pecially the last), during the last four or five years. They appear 

 so completely naturalized that they may be expected to outlast 

 the station itself, which, like Barnes Common, will soon be di- 

 verted to more utilitarian purposes than the production of foreign 

 weeds. 



Teibe 3. — Cotyledons conduplicate, embracing the dorsal radicle 

 (radicle included). 



SYNOPSIS OF THE GENEEA. 



Beassica. — Lower leaves lyrate, pinnatifid {glaucous). Pod linear, with a 

 cylindrical beak (style) . 



SiNAPis. — Leaves lyrate, pinnatifid, seldom glaucous. Beak angular, com- 

 pressed. 



DiPiOTAXis. — Pod compressed. Seeds in two rows. 



Eetjcastetim. — Seeds in one row, slightly compressed. 



Brassica, Lin. — Annual or biennial, usually glaucous, plants. 

 Root and lower leaves lyrate, pinnatifid; stem leaves entire, si- 

 niiate or toothed, sessile or clasping. Sepals erect, equal at the 

 base, or the lateral pair slightly gibbous, spreading. Stigma 

 entire, discoid, style conical, rarely four-cornered. Pod linear- 

 cylindrical or slightly quadrangular (the pod is four-angled in B. 

 nigra), often with a slight dorsal compression. Valves convex, 

 with a jsrominent dorsal nerve and anastomosing veins (veins 

 uniting). Seeds in one row, globular, not winged. 



B. oleracea, Lin. Sea-Cabbage. — e.b. 637. l.b.s. 113. 

 A 5. C. 10. Lat. 50-54. Alt. 0. Tern. 52-49°. 



Stems robust, thick, branched, glaucous and glabrous. Leaves 

 thick, the lower ones lyrate-pinnatifid, petiolate, the upper ob- 

 long, sessile, but scarcely clasping, crisp and toothed ; the upper- 

 most oblong-linear, slightly toothed or entire, all glaucous. 

 Flowers yellow or lemon-coloured, larger than they are in the 

 other species. Pods nearly cylindrical, smooth, with a thick 

 blunt beak, which is crowned with the sessile stigma. Seeds 

 large, globular. 



Sea-coast, Dover Cliffs, and many other parts of the coast of 

 England. Biennial; June- August. 



B. Rapa, Lin. Turnip. — e.b. 2176. l.b.s. — B.campestris, 114. 

 A. 14. C. 50. Lat. 50-57°. Alt. 0-200 yds. Tern. 51-47°. 



Stems usually stout, erect, glabrous (slightly hispid at the base), 

 glaucous, branched, leafy. Root and lower leaves lyrate-pinna- 

 tifid, slightly ciliated, petiolate ; the upper leaves oblong or ovate. 



