CEUCIFER^. 249 



2. A. MARiTiMUM, Lam. Encycl. i. 98 (1783); Linn. Sp. PI. ii. 652 

 (1753), under Clypeola. Perennial, decumbent, the numerous branches 

 1 ft. long or less; herbage softer than in the last, ostensibly glabrous, 

 under a lens showing a few appressed hairs: fl. 2 lines long, the broad 

 white petals twice the length of the deciduous sepals: pod orbicular, 



1 line broad, nearly glabrous, 2-seeded: pedicels slender, spreading. — The 

 Sweet Alyssum is spontaneous in many places, especially on the San 

 Francisco peninsula. 



3. PHYSARIA, A. Gray. Low herbs (our species perennial) silvery- 

 canesceut with a dense close stellate pubescence, entire or pinnatifid 

 leaves, and racemose yellow flowers of middle size; calyx more or less 

 persistent as in Alyst<u7n. Pods globose or ovoid, or the valves more 

 inflated and distended, nerveless. Style long, persistent. Seeds few, in 



2 rows, flattened, rarely somewhat margined: cotyledons accumbent. 



* Pods didymous. — Typical Phtsaria. 



1. P. didymocarpa, Gray, Gen. 111. i. 162 (1849); Hook. Fl. i. 49. t. 16 

 (1829), under \'esicaria. Leaves rosulately crowded on a short crown 

 or caudex, broadly spatulate, occasionally somewhat lyrate, those of the 

 decumbent flowering branches oblanceolate, entire: racemes short: pods 

 2 — 6 lines broad, /. e., more or less widely didymously-inflated, the parti- 

 tion narrow or nearly obsolete. — East of the Sierra, thence common 

 to Colorado. 



* * Pod globose or ovate. — Genus Le.squeeella, Wats. 



2. P. montana, Greene. Gray, Proc. Philad. Acad. 58 (1868), under 

 Vesicaria. Habit of the preceding: rosulate radical leaves orbicular or 

 obovate, long-petioled, those of the branches oblanceolate or spatulate, 

 entire, or with few teeth : fl. 3 lines long: pods oblong-ovoid, 2% lines 

 long, on slender recurved pedicels; style a third shorter. — On Lassen's 

 Peak, Leminon, thence eastward and northward. 



4. DRABA, Dioscorides. Small plants of various habit, annual or 

 perennial. Leaves entire or toothed. Flowers small, white or yellow. 

 Sepals equal. Filaments mostly flattened, without teeth. Pods oval, 

 oblong or linear, flat; valves nearly flat, nerveless or faintly l-nerved. 

 Seeds in 2 rows in each cell, wingless; cotyledons accumbent. 



* Slender annuals or biennials; leaves mostly radical. 



1. D. stenoloba, Ledeb. Fl. Ross. i. 154 (1842): D. hirta, var. siliquosa, 

 Ch. & Schl. Linnaea, i. 23 (1826). Radical leaves oblanceolate, }-2 — 1 in. 

 long, rather thin, acute, scarcely at all toothed, sparsely clothed with 

 stiff more or less branching or stellate hairs: stem 4 — 12 in. high, loosely 

 racemose almost throughout, glabrate above, canescently pubescent 

 below: petals bright or pale yellow, only 1 — 1^ lines long, obtuse: pods 



