68 CRUciFER^. (mustard family.) 



pods widely spreading, very slender, short-stalJced ; style scarcely any; seeds margin- 

 less. — New York and Illinois to Virginia and Kentucky. May, June. 



* * Erect and simple leafy-stemmed biennials, with white or whitish flowers, narrow 



but flattened ascending or erect pods, and wingless seeds. 



5. A. pktens, SuUiv. Downy with spreading hairs, erect (1°- 2° high) ; 

 stem-leaves oblong-ovate, acutish, coai'sely toothed or the uppermost entire, 

 partly clasping by the heart-shaped base ; petals (bright white, 4" long) twice 

 the length of the calyx ; pedicels slender, spreading ; pods spreading or ascending^ 

 tipped with a distinct style. — Central Ohio (rocky banks of the Scioto, Sulli- 

 vant), Pennsylvania (Huntingdon Co. to the Schuylkill, Porter) ; also in E. 

 Tennessee. April, May. 



6. A. hirstlta, Scop. Rough-hairy, sometimes smoothish, strictly erect 

 (l°-2° high) ; stem-leaves oblong or lanceolate, entire or toothed, partly clasp- 

 ing by a somewhat arrow-shaped or heart-shaped base ; petals (greenish-white) 

 small, but longer than the calyx ; pedicels and pods strictly upright ; style scarcely 

 any. — Eocks, common, especially northward. May, June. (Eu.) 



* * * E^'ect and simple leafy-stemmed biennials (l'^-3° high], with small idiitish 



flowers, recurved-spreading or pendulous flat pods (3' -4' long), and broadly 

 winged seeds, their stalks adherent to the partition. 



7. A. Isevig^ta/, DC. Smooth and glaucous, upright; stem-leaves partly 

 clasping by the arrow-shaped base, lanceolate or linear, sparingly cut-toothed or 

 entire ; petals scarcely longer than the calyx ; pods long and narroiv, recurved- 

 spreading on ascending or merely spreading pedicels. (This is also A. hetero- 

 phylla, Nutl. ) — Rocky places, Maine to Wisconsin and Kentucky. May. 



8. A. Canadensis, L. (Sickle-pod.) Stem upright, smooth above; 

 stem-leaves pubescent, pointed at both ends, oblong-lanceolate, sessile, the lower 

 toothed ; petals twice the length of the calyx, oblong-linear ; pods very flat, 

 scythe-shaped, hanging on rough-hairy pedicels (2" wide). — (A. falcata, Michx.) 

 Woods and ravines ; not rare, especially westward. June - Aug. 



* « » * Tcdl and leafy-stemmed biennials or pei-ennicds, icith rather showy flowers, 



the pink-purple petals long-claived ; anthers sagittate and lohen old arcuate- 

 recurved ; the widely spreading and rather short pods nearly iirete ; seeds mar- 

 ginless. (lODANTHrs, Torr. Sf Gray.) — Transition to Thelypodium and 

 Streptanthus. 



9. A. hesperidoides. Glabrous (l°-3° high), often branched above; 

 root-leaves round or heart-shaped, on slender petioles ; stem-leaves ovate-ob- 

 long and ovate-lanceolate (2' -6' long), membranaceous, veiny, sharply and 

 often doubly toothed, tapering to each end, the lower into a winged petiole, 

 sometimes bearing a pair or two of small lateral lobes ; pods on short diverging 

 pedicels, pointed by a short style. (He'speris pinnatifida, 21ichx. lodanthus 

 hesperidoides, Torr. ff Gray.) — Alluvial river-banks, Ohio, Kentucky and 

 southwestward. May, June. 



§ 2. TURRITIS, Dill. Seeds not so broad as the partition, occupying two more or 

 fess distinct rows in each cell, at least when young : strict and very leafy-stemmed 

 biennials ; the cauline leaves partly clasping by a sagittate base. ( Very gla- 



