120 CRUCIFERAE (MUSTARD FAMILY^ 



* Fruit indehisoent, often moniliform, 1-celled or transversely several-celled, the partitions spongy 



or pithy. 



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 ceU. 



16. Diplo taxis. Seeds ovoid, in 2 rows in each celL 



Tribe VII. SISYMBRlEAE. Stigma, when lobed, with lobes over tie placentae. Fruit lanoe- 

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



* Cauline 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. Alliaria. Glabrous 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 of fruit 1-nerved or, if not nerved, of thin-walled elongated cells. 



20. Braya. Pubescent. Leaves small, narrowly oblong or spatulate^oothed or subentire, ses- 



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

 +- +- 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 linear, not clasping, entire or 



toothed. 



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

 flattened parallel to a broad partition. Cotyledons accumbent (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, 

 i- Petals yellow. 



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



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



-i- -i- Petals white, pink, or purple, not yellow except sometimes near the brse. 

 ++ 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. Lunaria. Petals purple. Leaves deltoid-ovate. 



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

 = Peduncles radical, 1-flowered. 



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



eye. 



Peduncles not radical, several-flowered. 



29. Dentaria. Glabrous or pubescent with simple hairs. Rootstock 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-foliolate, petiolate. Seeds wiii_ 



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



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



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



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



