886 DRABA. [CLASS xv. ORDER i. 



raceme, of numerous flowers, becoming much elongated. Flowers 

 white, on spreading slender pedicles. Calyx of four ovate concave 

 equal pieces. Corolla of four ovate obtuse equal petals, wilh a short 

 claw. Stamens with simple awl-shaped filaments, 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, 

 wilh a slight marginal furrow. 



Habitat. Cliffs by the sea j 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.* 



GENUS XII. DRA'BA. LINN. Whitlow Grass. 

 Nat. Ord. CRCCIF'EIUE. Joss. 



GEN. CHAR. Silicula oval or oblong, with plane or sub-convex 

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

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

 entire, or bifid. Filaments simple. Named ^f^i, acrid or 

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

 * Petals lifid, white. Erophila, De Cand. Prod. 1, p. 172. 

 1. D. ver l na, Linn. (Fig. 1023.) Common Whitlow Grass. Scape 



* ALYSSTJM LINK. 



GEN. CHAR. Silicula sub-rotundate, ovate, with plane or convex valves, two 

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

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



equal. Petals entire. Filaments toothed. 



1. A. calyci'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. Nicholson, 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. 



