134 BEASSICACEAE. 



row, nearly equal. Petals 4, slightly larger than the sepals, yellow, spatulate. 

 Stamens 6: anthers ovoid. Ovary narrow: style very short or obsolete: stigma 

 2-lobed. Pod elongate. Seeds marginless. 



1. E. officinale L. Stems 3-12 dm. tall, the branches spreading: leaf -blades 

 2-20 cm. long, runcinate-pinnatifid, the segments irregular, entire, toothed, or 

 lobed: sepals 1.52 mm. long: petals yellow, spatulate: pods slender 10-16 mm. 

 long, slender-beaked. [Sisymbrium officinale (L.) Scop.] Common, in waste 

 places and on roadsides. Nat. of Eu. Spr. HEDGE-MUSTARD. 



9. NORTA Adans. Biennial, tall, sometimes diffusely branched, herbs. 

 Leaf-blades toothed or pinnatifid. Eacemes lax, becoming very lax in age, 

 the pedicels short and stout. Sepals rather narrow, spreading. Petals yellow, 

 exceeding the sepals. Stamens 6: anthers oblong-sagittate. Ovary narrow: 

 style very short : stigma 2-lobed. Pod slender, much-elongate, spreading. 



1. N. altissima (L.) Britton. Stems 1.5 m. tall or less, the branches spread- 

 ing, often divaricate: leaf -blades mostly 1-2 dm. long, deeply 1-2 -pinnatifid, 

 the segments narrow, entire or toothed: sepals 4-5 mm. long: petals pale-yel- 

 low, spatulate: pods very slender, elongate-linear, 6-10' cm. long, stout-beaked. 

 [Sisymbrium altissimum L.] Frequent, in fields and waste places. Nat. of 

 Eu. Sum. TUMBLE-MUSTARD. 



10. HESPERIS [Tourn.] L. Biennial or perennial herbs. Leaf -blades 

 entire, toothed, or rarely pinnatifid. Eacemes or panicles elongate. Sepals 

 4, broad. Petals 4, white or purple, with broad blades. Stamens 6 : anthers 

 oblong. Style very short or obsolete. Pod elongate. Seeds marginless. 



1. H. matronalis L. Stems 3-12 dm. tall, roughish-pubescent : leaves 2-15 

 cm. long; blades of the lower ones elliptic-oblanceolate, those of the upper 

 oblong or ovate-lanceolate, denticulate or rarely slightly pinnatifid: sepals 

 becoming 6-8 mm. long: petals 19-22 mm. long, the broadly obovate blades 

 about as long as the claws : pods 5-10 cm. long. Eather common, in fields 

 and on roadsides. Nat. of Eu. Spr. SOCKET. DAME 'S-VIOLET. 



11. ARABIDOPSIS Schur. Annual or perennial herbs. Leaf -blades 

 entire, toothed, or pinnatifid. Eaeemes elongate. Sepals 4, narrow. Petals 4, 

 spatulate, white. Stamens 6: anthers ovoid. Style short. Pod elongate. 

 Seeds oblong, marginless. 



1. A. Thaliana (L.) Britton. Plants 0.3-5 dm. tall, mainly branched through- 

 out, pubescent near the base: blades of the basal leaves oblong, elliptic, or 

 oblanceolate, 1.5-4.5 cm. long, entire or shallowly toothed: sepals 1-1.5 mm. 

 long: petals about twice as long as the sepals: pods linear-filiform, 10-15 mm. 

 long. [Stenophragma Thaliana, (L.) Celak.] Common, in waste places and 

 rocky woods. Nat. of Eu. Spr. MOUSE-EAR CRESS. WALL-CRESS. 



12. BARBAREA E. Br. Biennial or perennial herbs. Leaf -blades lyrate- 

 pinnatifid. Eacemes or panicles often dense. Sepals 4, unequal. Petals 4, 

 yellow, spatulate. Stamens 6: anthers oblong to ovoid. Style columnar: 

 stigma not dilated. Pod elongate. Seeds marginless. SCURVY-GRASS. 

 WINTER-CRESS. EOCKET. 



Capsules slender-pedicelled, obtusely 4-angled : leaf -segments 3-9. 



Capsules spreading or ascending : corolla bright-yellow. 1. B. Barbarea. 



Capsules erect and appressed : corolla pale-yellow. 2. B. stricta. 



Capsules stout-pedicelled, acutely 4-angled : leaf-segments 9-17. 3. B. verna. 



1. B. Barbarea (L.) MacM. Plants 2-9 dm. tall: leaves 5-15 cm. long, or 

 shorter above; blades of the lower ones pinnatifid, those of the upper ones 



