Draba 



CRUCIFERAE 



Thlaspi 



73. CRUCIFERAE Mustard Family +^7tf4 (Shih Tzu Hua K'o) 



Herbs with ivatery acrid sap and alternate lvs.: fls. comparatively small and 

 numerous, in racemes or corymbs; sepals and petals 4; stamens 6, tetradynamous; 

 pistil of 2 united carpels, becoming a capsule (silique or silicle), usually dehiscent by 

 two valves. About 200 genera with 1,800 species, widely distributed, especially in 

 temperate and cold regions; 25 genera and over 60 species in China. 



Key to the Genera 

 A. Fr. a short pod (a silicle). 

 B. Fr. strongly compressed. 



C. Fr. flattened parallel to the partition, oblong: pubescence 



stellate 1 . Draba 



CC. Fr. flattened at right angles to the partition. 



D. Pods orbicular, ovate, obovate or obcordate. 

 Pods more or less winged. 



Seeds several in each cell; pods bioadly winged. 2. Thlaspi 

 Seeds one in each cell; pods narrowly winged.. 3. Iberis 



Pods not winged; seeds one in each cell 4. Lepidium 



DD. Pods wedge-shaped, triangular 5. Capsella 



BB. Fr. somewhat compressed; carpels thickish, wrinkled, sepa- 

 rating at maturity as two nutlets 6. Coronopus 



BBB. Fr. globular, not at all compressed 7. Rorippa (in part) 



AA. Fr. more than 3 x as long as broad (a silique). 

 E. Petals yellow or orange yellow. 

 F. Lvs. pinnately cleft or divided. 

 Pod with beak. 



Pod with a beak 2-8 mm. long; seeds in one row in 



each cell : fls. 1 cm. or more across 8. Brassica 



Pod with a beak not over 1.5 mm. long; seeds in two 



rows in each cell: fls. much smaller 7. Rorippa (in part) 



Pod without beak: stigma sessile 9. Descurainia 



FF. Lvs. entire 



Fls. usually 2 cm. or more when open, orange yellow 



and brown 10. Cheiranthus 



Fls. usually smaller, light yellow 11 . Erysimum 



EE. Petals white or purple. 



Fr. dehiscent by two valves. 



Fls. purple, large 12. Orychophragmus 



Fls. white, medium sized or small 13. Cardamine 



Fr . indehiscent 14 . Raphanus 



1. Draba Linn. ^MM (Ting Li Shu) 

 Low herbs, generally stellate-pubescent: lvs. simple, mostly in basal rosettes: fls. 

 small, white or yellow: fr. strongly flattened parallel to the broad partition. 175 

 species, mostly in the northern hemisphere; two or more in China. (Old Greek name 

 for a cress.) 



1. Draba nemorosa Linn. i^H (T'ing Li) (G.M. 698). Erect herb, 5-30 cm. high; 

 fls. yellow, III-IV; pods flattened, elliptic-oblong. Eurasia, North America; 

 locally in Che., Ku. Open hills. 



2. Thlaspi Linn. Penny Cress tjf||f| (Hsi Ming Shu) 

 Erect glabrous herbs: basal lvs. forming a rosette; upper stem lvs. auriculate 



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