VOL. II.] 



MUSTARD FAMILY. 



ill 



Pods slightly winged above, orbicular or oval, about i" broad; petals present or none. 



Cotyledons accumbent; petals generally present. 4. L. Virginicum. 



Cotyledons incumbent; petals minute or wanting. 5. L. afietalum. 



Pods oblong, winged all around, longer than wide, about 2" high. 6. L. sativum. 



i. Lepidium campestre (L,.) R. Br. 

 Field or Cow Cress. (Fig. 1684.) 



Thlaspi campestre L,. Sp. PI. 646. 1753. 



Lepidium campestre R. Br. in Ait. f. Hort. Kew, 4: 



88. 1812. 



Annual or biennial, erect, io / -i8 / high, branch- 

 ing above, hoary-pubescent with scale-like hairs or 

 rarely nearly glabrous. Basal leaves oblong, or 

 spatulate-oblong, entire, or pinnatifid in the lower 

 part, obtuse, petioled, 2 / -3 / long; stem-leaves ob- 

 long or lanceolate, entire or slightly dentate, ses- 

 sile, clasping the stem by an auricled base; flowers 

 white or yellowish; pedicels rather stout, spread- 

 ing, 2 // -4 // long in fruit; pods very numerous, 

 forming dense elongated racemes, broadly ovate, 

 slightly curved upward, about equalling their 

 pedicels, or shorter, broadly winged at the apex, 

 notched, tipped with a minute style. 



In fields and waste places, New Brunswick and On- 

 tario to Virginia, and on the Pacific Coast, a bad weed 

 in the Middle States. Naturalized from Europe. 

 May-July. Also called Yellow Seed, Mithridate 

 Mustard, and Poor Man's Pepper. 



2. Lepidium Draba L. Hoary Cress. 

 (Fig. 1685.) 



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



Perennial, erect or ascending, io / -i8 / high, 

 hoary-pubescent, branched at the inflorescence. 

 Leaves oblong or lanceolate-oblong, obtuse, 

 slightly dentate or entire, i^ / -2 / long, the lower 

 petioled, the upper sessile and clasping; pedicels 

 slender, ascending or spreading, 3 // -6 // long in 

 fruit; flowers white, about i // -2 // broad; pods 

 very broadly ovate, or cordate, i%" long, -2" 

 broad, arranged in short corymbose racemes; 

 valves distinct, papillose, keeled, wingless, tipped 

 with a slender style y^ ff -i /f long. 



Near Astoria, N. Y., and on ballast about the sea- 

 ports. Also in Colorado and California. Fugitive 

 from Europe. Native also of Asia. April-June. 



3. Lepidium ruderale L. Roadside or 

 Narrow-leaved Pepper-grass. (Fig. 1686.) 



Lepidium ruderale L,. Sp. PI. 645. 1753. 



Annual, erect, f>'-i$' high, glabrous, wiry, 

 freely branching. Basal and lower leaves oblong 

 in outline, i'-4' long, i-2-pinnatifid into linear 

 or oblong obtuse segments; upper leaves smaller, 

 entire or with a few lobes; flowers %" broad or 

 less, greenish; petals none; stamens 2; pods flat, 

 not margined, about \" in length, short-oval 

 or suborbicular; pedicels spreading or some- 

 what ascending, very slender, \%"-2" long in 

 fruit; valves sharply keeled, barely winged; 

 cotyledons incumbent. 



In waste places, on ballast and along roadsides 

 about the cities, Nova Scotia to Texas. Naturalized 

 from Europe. Has the odor of Wart-cress. Occurs 

 also in Australia. Summer. 



