886 DUABA. [cr.Ass xv. order i. 



raceme, of numerous flowers, becoming much elongated. Flowers 

 white, on spreadinj* slender pedicles. Calyx of four ovale concave 

 equal pieces. Corolla of four ovale obtuse equal petals, with a short 

 claw. Stamens with simple awl-shaped filaynents, having between 

 them at the base eight glands, the yellow anthers of two lobes. Fruit 

 a sub-ovate silicula, with flat compressed valves^ smooth, two celled, 

 each cell with a solitary pendulous seed^ ovate, compressed, pale brown, 

 with a slight marginal furrow. 



Habitat. — Cliffs by the sea ; Devonshire, Cornwall, and near Aber- 

 deen, in Scotland. 



Perennial ; flowering in August and September. 



This plant, though common on almost all the sea coasts of the Con- 

 tinent, and especially the shores of the Mediterranean, and flowering 

 there in sheltered situations almost all the year round, has but 

 slender claims to the rank of a native plant of our coasts, but seems 

 now to have established itself as a naturalized plant. It is frequently 

 cultivated in gardens, and much esteemed from its continuing a long time 

 in flower, and the pleasant odour which it exhales.-i^ 



GENUS XII. DRA'BA.— Linn. Whitlow Grass. 



Kat. Ord. Cuucif'eu^. Juss. 



Gen. Char. Silicula oval or oblong, with plane or sub-convex 

 valves, two celled, many seeded. Seeds not with a margin. Coty- 

 ledons accumbent.— (e Fig. 1, p. 871.) — Calyx equal. Petals 

 entire, or bifid. Filaments simple. — Named ^^ocjSv, acrid or 

 biting, from the acrid properties of some of the species. 

 ^- Petals bijid, ivJiiie. Erophila, De Cand. Prod. 1, p. 172. 

 1. D. ver'nttf Linn. (Fig. 1023.) Common Whitloiv Grass. Scape 



* ALYSSUiM.— Linn. 



Gen. Char Silicula sub-rotundate, ovate, with plane or convex valves, two 



celled, two to four seeded. Seeds compressed, sometimes with a mem- 

 branous margin. Cotyledons accumbent. — (c Fig. 1, p. 871.) — Calyx 

 equal. Petals entire. Filaments toothed. 

 1. A. cali/ci'num, Linn. Stem herbaceous, ascending; calyx persistent; 

 filaments toothed ; silicula orbicular, with a narrow margin, clothed with very 

 short close starry pubescence ; style short ; leaves lanceolate, hoary. 



Habitat. — Dry sandy fields between Arbroath and sands of Barry, Scotland. 

 .--Dr. r^icholson, 1835. 



Annual ; flowering in May and June. 



Specimens of this plant were sent to us, in 1835, from the above station ; but 

 some doubt remains as to its claim even to be considered a naturalized plant. 

 It is not unfrequent on the Continent, especially in the Southern parts. 



