CRUCIFERAE. 445 



the basal and lower ones petioled, narrowly oval or oblong, 5-10 cm. long, ihe 

 upper sessile, linear, lanceolate or oblong-lanceolate, acute or acuminate ; flowers 

 pink, in short racemes; pedicels slender, 4-8 mm. long; petals obovate or spatulate, 

 long-clawed ; pods about 2.5 cm. long and I mm. wide ; stipe very short ; style 

 slender, nearly 2 mm. long. Neb. and Wyo. to Ore., Utah and N. Mex. July- 

 Sept. 



3. subulXria l. 



Small annual aquatic submersed herbs, with basal linear subulate leaves, and 

 minute racemose white flowers. Silicles short-stipitate, oblong or elliptic, the 

 valves convex, ribbed on the back. Stigma sessile, entire. Seeds few, in 2 rows 

 in each cell, marginless. Cotyledons incumbent, curved above their base. [Latin 

 awl. from the awl-shaped leaves.] A monotypic genus of the northern hemis- 

 phere. 



1. Subularia aquatica L. Water Awlwort. (I. F. f. 1683.) Tufted, 

 glabrous. 2-10 cm. high, growing in shallow water. Flowering scape simple, 

 lateral; leaves nearly cylindric, 1-3 cm. long; flowers few, distant; pedicels slender, 

 2-6 mm. long in fruit; pods 2-3 mm. long. In clear, cold lakes, Newf. to Br. Col., 

 Me.. Vt. and Ont., south in the Rocky Mts. to Wyo., and to Cal. Also in Europe 

 and Siberia. June-Sept. 



4. LEPIDIUM L. (See Appendix.; 



Erect or rarely diffuse herbs, with pinnatifid lobed or entire leaves and race- 

 mose white or whitish flowers. Stamens often fewer than 6. Petals short, some- 

 times none. Silicles oblong or obovate, flattened contrary to the partition, winged 

 or wingless; valves keeled, dehiscent. Seeds solitary in each cell, flattened; coty- 

 ledons incumbent or rarely accumbent. [Greek, a little scale, from the flat scale - 

 like pods.] About 65 species, widely distributed. In addition to the following, 

 about 16 others occur in western N. Am. 



Stem-leaves clasping by an auriculate base. 



Pods broadly ovate, winged. 1. L. ccunpestre. 



Pods wingless, broader than long. 2. L. Draba. 



Stem-leaves petioled or sessile, not clasping. 



Pods and seeds entirely wingless ; petals none. 3. L. ruderale. 



Pods slightly winged above, orbicular or oval, about 2 mm. broad ; petals present or 

 none. 



Cotyledons accumbent; petals generally present, 4. L. Virginicion. 



Cotyledons incumbent; petals minute or wanting. 5. L. ape 7 alum. 



Pods oblong, winged all around, longer than wide, about 4 mm. high. 



6. L. sativum. 



1. Lepidium campestre (L.) R. Br. Field or Cow Cress. (I. F. f. 1684O 

 Annual or biennial, erect, 2-4.5 dm. high* branching above, hoary-pubescent with 

 scale-like hairs or rarely nearly glabrous. Basal leaves entire, or pinnatifid in the 

 lower part, obtuse, petioled, 5-8 cm. long; stem-leaves oblong or lanceolate, entire 

 or slightly dentate, sessile, clasping ; flowers white or yellowish ; pedicels rather 

 stout, spreading. 4-8 mm. long in fruit ; pods forming dense elongated racemes, 

 broadly ovate, slightly curved upward, broadly winged at the apex, notched, tipped 

 with a minute style. In fields and waste places. N. S. and Ont. to Va., Kans., 

 and on the Pacific Coast, a bad weed in the Middle States. Nat. from Europe. 

 May-July. 



2. Lepidium Draba L. Hoary Cress. (I. F. f. 1685.) Perennial, erector 

 ascending. 2-4.5 dm. high, hoary-pubescent. Leaves oblong or lanceolate-oblong, 

 obtuse, slightly dentate or entire. 3-5 cm. long, the lower petioled, the upper sessile 

 and clasping; pedicels 6-12 mm. long in fruit ; flowers white, about 4 mm. broad; 

 pods broadly ovate, or cordate, 3 mm. long, in short racemes ; valves papillose, 

 keeled, tipped with a style 1-2 mm. long. Near Astoria and Syracuse. N. Y., 

 and on ballast about the seaports. Also in Colo, and Cal. Fugitive from Europe. 

 April-June. 



3. Lepidium ruderale L. Roadside Pepper-grass. (I. F. f. 1686.) An- 

 nual. 1.5-4 dm. high, glabrous, wiry. Basal and lower leaves oblong in outline. 

 2-10 cm. long. I -2-pinnatifid into linear or oblong obtuse segments; upper leaves 



