164 Cruciferae 



Family 35. CRUCIFERAE. MUSTARD FAMILY. 



Herbs or rarely suffrutescent with acrid juice, alter- 

 nate leaves and racemose or corymbose flowers. Sepals 

 4, deciduous or persistent, the 2 outer narrow, the inner 

 similar, concave or saccate at base. Petals 4, rarely 2 

 or none, hypogynous, cruciate, nearly equal, generally 

 clawed. Stamens 6, rarely fewer, hypogynous, tetrady- 

 namous. Pistil 1, compound, consisting of 2 united car- 

 pels, the parietal placentae united by a dissepiment ; style 

 generally persistent, sometimes none ; stigma discoid or 

 more or less 2-lobed. Fruit a silique or silicle, usually 

 2-celled, 2-valved or rarely indehiscent. Endosperm 

 none ; cotyledons incumbent, accumbent or conduplicate. 



** Pods dehiscent into 2 valves to the base. 

 Pods elongated-linear, at least twice as long as wide. 



Flowers white or purplish, or yellow in some species of Roripa. 

 Subaquatic or marsh plants. 



Seeds in 1 row in each cell. 12. CARDAMINE. 



Seeds in 2 rows in each cell. 11. RORIPA. 



Not aquatic or marsh plants. 



Rootstocks tuberous. 13. DENTARIA. 



Roots fibrous. 

 Petals fiat. 



Pods usually compressed, seeds flat, winged. 



22. ARABIS. 

 Pods terete; seeds oblong or globose, wingless. 



2. THELYPODIUM. 

 Petals undulate-crisped or twisted. 



Pods terete or nearly so; cotyledons incumbent. 



3. CAULANTHUS. 

 Pods compressed; cotyledons accumbent. 



4. STREPTANTHUS. 

 Flowers yellow. 



Pods borne on a long stipe. 1. STANLEYA. 

 Pods terete or 4-angled, sessile or short stipitate. 

 Pubescence simple or none. 

 Pods spreading. 



Seeds globose or oblong. 



Seeds in 2 rows. 7. DIPLOTAXIS. 



Seeds in 1 row. 8. BRASSICA. 



Seeds flat. 10. BARBAREA. 



Pods erect, appressed to the stem. 6. ERYSIUM. 

 Pubescence branched or stellate. 



Leaves entire or faintly toothed. 23. CHEIRANTHUS. 



Leaves deeply 2-pinnatifid. 21. SOPHIA. 



Pods flat. 14. TROPIDOCARPUM 



