164 THE FLORA. 



S. pinnatifida. A prostrate, weed-like plant, common at the South, in fields and on 

 river-banks. Leaves divided in a pinnate manner, into oblong, toothed lobes. 

 Flowers obscure, with scarcely any petals. Silicles flattened, notched at apex, 

 wrinkled on the surface. Feb.-July. 



6. DKA'BA. Wliitlow-grass. 



Calyx equal at base. Petals equal. Filaments without teeth. Silicle 

 oval-oblong, entire, flattened parallel to the broad partition. Cells 2, 

 many-seeded. Seeds not margined. — Low herbs, with small white ©r 

 yellow flowers in racemes. (See Fig. 396.) 



§ Petals 2-cleft, white. Leaves all radical 1 



§ Petals entire or merely notched. Stems more or less leafy. . . .a 



a Style present. Plants perennial 2, 3 



a Style none. Plants annual or biennial. . . .b 



b Pedicels as long or longer than the pod. . . .4, 5 

 b Pedicels shorter than their pods .... 

 1 D.verna. Spring W. Leaves oblong, hairy. Scape 1-5'' high, (See Fig. 396.) 

 2 D. arabi'sans. Mock W. Leaves minutely toothed. Silicle twisted, longer than 



the pedicel, oblong-lanceolate, 4-6'''' long. Lake shores. (Figs. 155-159.) 

 8 D. ramosis'sima. Bushy W. Leaves with remote and slender teeth. Silicle as 

 long as its pedicel, style half as long. Flowers white. Eocks. 

 * 4 D. nemora'lis. Wood W. Petals notched at end. Pod half as long as ilR 

 pedicel. Seeds near 30. Flowers yellowish-white. N-W. 

 4 D. brachycar''pa. Short-f I'uitedj TV. Petals entire. Pod as long as pedicel, 

 10-12-seeded. Leaves round-ovate. S. W. March, April. 



5 D. Carolinia'na. Leaves round-ovate, entire. Pods linear, in a sort of corymb. 



Flowers white. Plant hispid, 1-3'' high. E. S. April-June. 



6 D. cuneifo'lia. Wedge-leaved W. Leaves wed,i;e-oblong. Pods lance-oblong, 20- 



30-seeded, racemed. Plant 3-8' high. S-W. 



7. AE'ABIS. Rock Cress. Sickle-pod. 



Sepals erect. Petals clawed, entire. Silique linear, flattened, valves 

 one-veined in the middle. Seeds in a single row in each cell. Flowers 

 white. Aprilr-June. 



§ Leaves all (or at least the radical) pinnatifid 1, 2 



§ Leaves all undivided ; toothed or entire, often clasping. . . .a 



a Siliques short (6-12^'') and straight. Seeds not winged 3, 4 



a Siliques longer (1-2''), straight or curved. Seeds not winged 5, 8 



a Siliques long (30> curved, hanging. Seeds winged 7, 8 



