420" CRUCIFEEAE (^MUSTARD FAMILY) 



* Fruit indehiscent, often moniliform, 1-celled or transversely several-celled, the pai-titions spongy 



or pith}'. 



14. Raphanus. Petals large, pale yellow or purplish. Fruit stout, beaked. 



* * Fruit longitudinally 2-celled, dehiscent. 



15. Brassica. Seeds globose, in a single row in each cell. 



16. Diplotaxis. Seeds ovoid, in 2 rows in each cell. 



Tribe VII. SISYMBRIeAE. Stigma, when lobed, with lobes over the placentae Fruit lance- 

 oblong to Unear, 2-celled, dehiscent Cotyledons incumbent. 



* Oauiine hairs simple or stellate, not regularly bifid. 

 +- Petals small (not over 1 cm. long), yellow, white, or pale purple. 



17. Conringia. Glabrous. Leaves elliptical, entire, cordate, sessile. 



18. Alllaria. Ciiabrous or pubescent. Leaves orbicular or reniform, broadly cordate, toothed, 



petiolate. 



19. Sisymbrium. Pubescent. Leaves various but not as in either of the two preceding. Parti- 



tion (it fruit 1-nerved or, if not nerved, of thin-walled elongated cells. 



20. Braya. Pubescent. Leaves small, narrowly oblong or spatiiiate, toothed or subentlre, ses- 



sile. Partition of the fruit without midnerve, its cells thick-walled. 

 -»- -H Petals large (1.5-2 cm. long), deep purple. 



21. Hesperis. Tall. Leaves ovate-lanceolate, denticulate, the lower long-petioled. Pods very 



long and slender. 



* * Cauline hairs 2-branched, the branches vertical and appressed. 



22. Erysimum. Petals yellow or orange. Leaves lanceolate to hnear, not clasping, entire or 



tootlu'd. 



Tribe VIII. ARABfDEAE. Fruit 2-celled, dehiscent, globose to long and slender, terete or 

 flattened [larallel to a broad partition. Cotyledons accunibent (in Leavemcorthia the embryo 

 sometimes nearly straight). 



* Fruit globose to ovoid or oblong and terete ; petals yellow or white. 



23. Radicula. Flowers small. Leaves toothed, lobed, or pinnate. 



* * Fruit either terete and elongated or elliptic- or linear-oblong and strongly compressed parallel 



to a broad partition. 

 +- Petals yellow. 



24. Barbarea. Pods slender, terete or nearly so. Biennials. 



25. Selenia. Pods broadly elliptic-oblong, very flat. Low annual. 



-J- -«- Petals white, pink, or purple, not j-ellow except sometimes near the base. 

 ■H- Pods long and slender, not at all compressed parallel to the partition. 



26. lodanthUS. Lateral sepals somewhat horned on the back near the apex. Petals broadly 



spatulate, purple. 



++ ++ Pods elliptic-oblong or lance-elliptic, about 2.5 cm. broad, very flat. 



27. Lnnaria. Petals purple. Leaves deltoid-ovate. 



++++++ Pods distinctly compressed parallel to the partition, but not over 1 cm. broad. 



= Peduncles radical, 1-flowered. 



98. Leavenworthia. Pods oblong, sometimes torulose. Flowers purple or white with a yellow 



ej'e. 



= = Peduncles not radical, several-flowered. 



29. Dentaria. Glabrous or pubescent with simple hairs. Eootstock fleshy, toothed, or monili- 



form-tuberous. Stem naked below, bearing near the middle 2-3 verticillate or alternate 

 leaves ; these for the most part palmately 3-7-f()liolate, petiolate. Seeds wingless. 



30. Cardamine. Glabrous or pubescent with simple hairs, fibrous-rooted, rarely tuber-bearing. 



Stem leafy ; leaves alternate, from ovate and crenate-dentate to pinnate. Seeds wingless. 



81. Arabis. Usually pubescent, some or all of the hairs being branched. Roots fibrous ; no 



tubers. Seeds usually winged or •.ving-margined. Leaves alternate simple or pinnatifid. 



