CRTJCIFER^E. (MUSTARD FAMILY.) 19 



the largest, entire or coarsely sinuate-toothed or lobed, often cordate at base ; 

 radical leaves mostly simple and cordate-reniform : pods obtuse or scarcely 

 beaked with a short style, ascending. — Proc. Am. Acad. x. 339. C. pau 

 cisecta of Hayd. Rep. 1870, 1871, 1872. From Wyoming to California and 

 Oregon. 



3. C. hirsuta, L. Stem 3 to 12 inches high, erect or ascending from a 

 spreading cluster of root-leaves : leaflets 3 to 7 pairs, rounded ; those of the 

 upper leaves oblong or linear and often confluent: flowers small: pods erect or 

 ascending in line with the pedicels ; «tyle very short or almost none. — From 

 Colorado to Alaska and eastward across the continent. 



3. PAEETA, R. Br. 



Style rather short ; lobes of the stigma connate. Seeds flat, orbicular, with 

 a broad membranous border. — Low herbs, with thick perennial roots and 

 numerous scapes with racemed flowers. 



1. P. nudieaulis, Regel. Rootstock fusiform: scape 4 to 6 inches 

 high : leaves broadly lanceolate, incisely toothed : petals rose-color or purple, 

 retuse : pods broadly linear, erect, slightly incurved, somewhat constricted 

 between the seeds, which are slightly corrugated. 



Var. aspera, Regel. Pilose with glandular hairs. 



Var. glabra, Regel. Whole plant glabrous. — Both varieties are included 

 in the P. macrocarpa of Bot. King's Exp. 14 and Torr. & Gray, Fl. i. 88. 

 Near the summit of one of the highest peaks of the TJintas ( Watson). 



4. ARAB IS, L. Rock Cress. 



Anthers short, hardly emarginate at base. Stigma entire or somewhat 

 2-lobed. Pod linear. Seeds flat and usually winged. — Erect, with perpen- 

 dicular roots and undivided leaves, the cauline usually clasping and auricled 

 at base. 



# Biennials : pods erect or ascending : flowers small, white or nearly so. 



1. A. perfoliata, Lam. Glaucous: stem stout, usually simple, 2 to 4 

 feet high, mostly glabrous but often hirsute toward the base : lower leaves spatu- 

 late, sinuate-pinnatiflid or toothed ; the cauline entire, ovate or ovate-lanceolate, 

 clasping by the sagittate base : petals little exceeding the sepals : pods erect and 

 usually oppressed, narrowly linear; style short: seeds in two rows, narrowly 

 winged or wingless. — Across the continent and far northward. 



2. A. hirsuta, Scop. Rough-hairy, sometimes smoothish, 1 to 2 feet high : 

 leaves often rosulate at the base ; the cauline ovate to oblong or lanceolate, 

 entire or toothed, partly clasping by a somewhat sagittate or cordate base : petals 

 greenish-white, longer than the sepals : pedicels and pods strictly upright ; style 

 scarcely any : seeds in one row, wingless. — Colorado and northward, and east- 

 ward across the continent. 



3. A. spathulata, Nutt. Hirsute, dwarf and somewhat cespitose, about 

 4 inches high : root thick, crowned with vestiges of former leaves and stems : 

 leaves spatulate-oblong, entire; radical leaves on rather long petioles: petals 

 about twice the length of the sepals : pedicel about half the length of the pod, 

 which is rither short, diverging, pointed with a distinct slender stijle : seeds with 



