258 BRASSICACEAE 



9. HYMENOPHYSA C. A. Mey. in Ledeb. Fl. Alt. 3: 180. 1831. 



Perennial herbs, pubescent with simple hairs, the stems branching-, leafy. Leaves 

 sessile or clasping, entire or dentate. Flowers in corymbose racemes, on slender pedicels, 

 white. Sepals alike at base, scarious-margined. Stamens 6. Silicle subglobose and in- 

 flated, dehiscent or indehiscent; style slender. Seeds 2-4, ellipsoid, faintly reticulate; 

 cotyledons incumbent. 



A monotypic Old World genus. 



1. Hymenophysa pubescens C. A. Mey. Globe-podded Hoary Cress. Fig. 1970. 



Hymenophysa pubescens C. A. Mey. in Ledeb. Fl. Alt. 3: 181. 1831. 



Perennial with short branching caudex, the flowering stems branching, at least above, leafy. 

 Leaves oblong, 10-35 mm. long, acutish or obtuse at apex, auriculate-clasping at base, finely 

 serrate-dentate, cinereous-puberulent ; racemes corymbose ; flowers 2 mm. high, rather crowded ; 

 fruiting pedicels slender, 3-8 mm. long; pods subglobose, 3-4 mm. in diameter, puberulent; 

 seeds brown, faintly reticulate. 



Fields, especially in alfalfa, and waste land, adventive from Eurasia; eastern Washington, Klamath Basin, 

 Oregon, and Sacramento Valley, California. June-Aug. 



10. LEPIDIUM [Tourn.] L. Sp. PI. 643. 1753. 



Erect or diffuse, annual, biennial, or perennial herbs, or rarely suffrutescent, with 

 pinnatifid, lobed or entire leaves, and racemose, white or greenish flowers. Petals small, 

 rarely wanting. Stamens often fewer than 6. Stigmas sessile or nearly so. Silicles oblong 

 or obovate, flattened contrary to the partition, more or less emarginately winged at the 

 apex; valves keeled, dehiscent. Seeds 1 in each cell, flattened; cotyledons incumbent or 

 rarely accumbent. [Greek, meaning a little scale, from the flat scale-like pod.] 



A genus of about 65 species, of wide geographical distribution. Type species, Lepidium latifolium L. 



Stigmas on slender, sometimes short but evident, persistent styles. 

 Pods not notched or winged at the apex. 



Pods cordate at base; stem leaves clasping; flowers white. 1. L. Draba. 



Pods not cordate at base; stem leaves not clasping; flowers yellow. 2. L. Jaredii. 



Pods notched at the apex. 



Flowers yellow. 3. L. flavutn. 



Flowers white. 



Plants annual, pubescent; introduced species. 



Pods not winged; upper leaves cordate-clasping. 4. L. perfoliatum. 



Pods winged all around; upper leaves sagittate-clasping. 5. L. campestre. 



Plants perennial or suffrutescent; native species. 

 Stems herbaceous; pods oval, 2—4 mm. long. 



Plants puberulent or hirsutulous; pods 2 mm. long. 6. L. montanum. 



Plants glabrous; pods 3.5-4 mm. long. 7. L. Jonesii. 



Stems woody below; pods obcordate, 6 mm. long. 8. L. Fretnontii. 



Stigmas sessile or subsessile; style, if any, short and thick. 



Pods merely emarginate at the apex (rather deeply so and somewhat winged in bipinnatifidum). 

 Pedicels slender, terete or nearly so. 



Petals present, equaling or exceeding the sepals. 



Cotyledons accumbent. 9. L. zirginicttm. 



Cotyledons incumbent. 



Petals narrowly spatulate, about equaling the sepals. 



Basal leaves pinnately parted, the segments often toothed. 10. L. Menziesii. 



Basal leaves merely toothed or sometimes somewhat pinnatifid. 



11. L. texanum. 



Petals obovate, exceeding the sepals. 12. L. idahoense. 



Petals none, or if present, rudimentary and much shorter than the sepals. 13. L. densiflorum. 

 Pedicels strongly flattened. 



Pods pubescent. 14. L. lasiocarpum. 



Pods glabrous. 



Petals present; fruiting raceme loose. 15. L. nitidum. 



Petals none; fruiting raceme rather dense. 16. L. bipinnatifidum. 



Pods conspicuously winged at apex with two lobes or teeth; plants mostly of alkaline or saline soils. 

 Wings of the pod approximate, the sinus very narrow; pods strongly reticulate. 



Body of the pod little exceeding the wings in length. 17. L. latipes. 



Body of the pod much exceeding the short wings. 18. L. dictyotum. 



Wings of the pod represented by acute, divergent teeth; pods finely reticulate. 



Teeth very short, widely divergent. 19. L. oxycarputn. 



Teeth about as long as the body of the pod. 20. L. acutidens. 



1. Lepidium Draba L. Hoary Cress. Fig. 1971. 



Lepidium Draba L. Sp. PI. 645. 1753. 

 Cardaria Draba Desv. Journ. Bot. 3: 163. 1813. 



Perennial, hoary-pubescent throughout, the stems erect or ascending, 2-5 dm. high, branched 



