Vor. II.] MUSTARD FAMILY. 149 
7. Arabis hirsuta (L.) Scop. Hairy 
Rock-cress. (Fig. 1777.) 
Turritis hirsuta V,. Sp. Pl. 666. 1753. 
Arabis hirsuta Scop. Fl. Carn. Ed. 2, 2: 30. 1772. 
Stem strictly erect, nearly simple, 1°-2° high, 
rough-hairy or nearly glabrous. Basal leaves on 
margined petioles, obovate or spatulate, obtuse, den- 
tate or repand, 1/—2’ long; stem-leaves sessile, clasp- 
ing by an auricled base, lanceolate or oblong; pedicels 
nearly erect, or appressed, 3/’-6’’ long in fruit; flowers 
2//-3/’ long, white or greenish-white; petals more 
or less longer than the calyx; pods narrowly linear, 
erect or appressed, 1/-2’ long, about 14’’ wide; 
seeds I-rowed, or when young obscurely 2-rowed, ob- 
long or nearly orbicular, narrowly margined; style 
very short. 
In rocky places, New Brunswick to British Columbia, 
south to the mountains of Georgia, Arizona and Cali- 
fornia. Also in Europe and Asia. May-Sept. 
8. Arabis laevigata (Muhl.) Poir. 
Smooth Rock-cress. (Fig. 1778.) 
Turritis laevigata Muhl.; Willd. Sp. Pl. 3: 543. 18o0r. 
A. laevigata Poir.in Lam.Encycl.Suppl. 1: 414. 1810. 
Glaucous, entirely glabrous, 1°-3° high, nearly 
simple. Basal leaves petioled, spatulate or ob- 
ovate, sharply and deeply dentate, 2/—3’ long; 
stem-leaves sessile, lanceolate, or the upper lin- 
ear, acute, entire or dentate, clasping by an 
auricled or sagittate base; pedicels ascending or 
spreading, 4/’-5’’ long in fruit; flowers greenish 
white, 2/’-3’’ high; petals nearly twice the 
length of the calyx; pods 3/-4/ long, 1/’ wide, 
recurved-spreading ; seeds in I row, oblong, 
broadly winged; style almost none. 
In rocky woods, Quebec to Lake Huron and Min- 
nesota, south to Georgia and Arkansas. Ascends to 
5000 ft. in Virginia. April-May. 
Arabis laevigata laciniata T. & G. Fl. N. A. 1:82. 1838. 
Stem-leaves deeply and narrowly laciniate- 
toothed. Kentucky. 
Arabis laevigata Burkii Porter, Bull. Torr. Club, 17:15. 1890. 
Leaves linear or lanceolate, elongated, entire or sparingly toothed, not auricled at the base; 
flowers one-half the size of the type; petals equalling the sepals. Pennsylvania to North Carolina. 
g. Arabis Canadénsis I, Sickle-pod. 
(Fig. 1779.) 
Arabis Canadensis \,. Sp. Pl. 665. 1753. 
Stem nearly simple, 1°-3° high, pubescent below, 
glabrous above. Basal leaves narrowed into a petiole, 
blunt but sometimes acutish, dentate or lyrately lobed, 
3’-7’ long; stem-leaves sessile, not clasping, lanceo- 
late or oblong, narrowed at each end, toothed, or the 
upper entire, pubescent; pedicels hairy, ascending and 
2/’-4’’ long in flower, spreading or recurved and 4//— 
6’’ long in fruit; flowers greenish-white, 2’/-3/’ long; 
petals twice as long as the calyx; pods 2/-3'4’ long, 
1%’ broad, scythe-shaped, pendulous; seeds in 1 row 
in each cell, oblong, wing-margined; style almost none. 
In woods, Ontario to Georgia, west to Minnesota, Arkan- 
sas and Texas. Ascends to 4200 ft. in North Carolina. 
June-Aug. 
