16 CEUCIFEE^E. (MUSTARD FAMILY.) 



10. Barbarea. Pod somewhat 4-angled, pointed. Seeds oblong ; cotyledons nearly ac- 



cumbent. Anthers short, oblong. Leaves lyrately-piimatifid. A smooth marsh 

 perennial 



11. Sisymbrium. Pod nearly terete, short-pointed or obtuse. Seeds oblong ; cotyle- 



dons incumbent Anthers linear-oblong, sagittate. Mostly annual, with finely dis- 

 sected or entire leaves. 



12. Smelowskia. Pod short, 4-angled, pointed at each end. Alpine perennials with 



narrowly pinnatifid leaves ; otherwise as Sisymbrium. 



t- +- -i- Pod oblong-cylindric to globose ; valves strongly convex, nerveless ; seeds in 2 

 rows, cotyledons accumbent. 1 



13. Nasturtium. Pod oblong or short-linear. Flowers white or yellow. Smooth or 



somewhat hispid. 



14. Vesicaria. Pod ovate to globose. Seed flattened. Flowers yellow. Densely stellate- 



canescent. 

 * # * Pod more or less flattened contrary to the partition, which is narrower than the valves ; 



seeds not winged. 



i- Valves 1-nerved or obtusely carinate, not winged ; cells several-seeded ; cotyledons in- 

 cumbent : flowers white. 



15. Subularia. Pod ovoid, slightly compressed. A dwarf stomless aquatic, smooth, 



with tufted subulate leaves. 



16. Capsella* Pod obcordate or oblong, much compressed. Nearly smooth annuals. 



*- - Valves acutely carinate or winged ; cells few (1 to 5)-seeded ; cotyledons accumbent 

 (mostly incumbent in Lepidiu/n) : flowers white. 



17. Thlaspi. Pod cuneate-oblong ; valves sharply carinate ; cells 2 to 4-seeded. A smooth 



alpine perennial with entire leaves. 



18. Lepitlium. Pod orbicular or obovate, 2-winged at the summit ; cells 1 to 2-seeded. 

 --*- Valves inflated, nerveless ; cells several-seeded ; cotyledons accumbent : flowers 



yellow. 



19. Physaria. Pod didymous ; cells nearly globular. Stellate-cancscent perennials with 



entire leaves. 



II. Pod of 2 indehiscent cells, separating at maturity from the persistent axis. 2 



20. Biscutella* Cells flat, nearly orbicular, 1-seeded. Flowers rather large. Stigma 



dilated or conical, nearly sessile. 



1. DEABA, L. WHITLOW-GRASS. 



Sepals equal. Filaments mostly flattened, without teeth : anthers rounded 

 or oval. Leaves entire or toothed. 



* Sfems scape-like, leafless (or perhaps 1 or2-leaved). 



1. D. Stellata, Jacq. Scape with a single leaf, pubescent: leaves oblong- 

 oval, tomentose with a short stellate pubescence : flowers white. : pedicels puberulent : 

 pods oblong. Uinta and Teton Mountains, and far northward. 



Var. nivalis, Regel. Scape naked or sometimes with one or two leaves, 

 pubescent : leaves oblanceolate to obovate, canescent with a stellate pubescence : 

 pods narrowly oblong, and, with the pedicels, becoming glabrous. D. nemorosa, 

 var. alpina, of the Fl. Colorado. High peaks about Mt. Lincoln, Colorado, 

 and in Arctic America. 



Var. Johanms, TCegel. Scape naked or with a single leaf, glabrous: 

 leaves ovate, with a short woolly pubescence : pods long, linear, and with the pedi- 



1 Camelina, an introduced genus, is distinguished by its pear-shaped pod, 1-nerved valves, 

 incumbent cotyledons, and small yellow flowers. See foot-note, p. 25. 



2 Raphanus, an introduced genus, is known by its elongated 1-celled or transversely- 

 jointed pod, which is attenuated above. See foot-note, p. 27. 



