11. Arabis Drummóndii A. Gray. Drum-Mond's Rock-Cress

Fig. 2079

A. Drummondii A. Gray, Proc. Am. Acad. 6: 187. 1866.

Turritis stricta Graham, Edinb. New Phil. Journ. 1829: 350. Not Arabis stricta Huds.

Biennial, glabrous throughout, or the basal leaves sometimes sparingly pubescent; stem erect, 8'-3° tall, slightly glaucous. Basal leaves ob-lanceolate, long-petioled, dentate or entire, those of the stem lanceolate to oblong, erect or nearly so, entire, sessile, sagittate; flowers pink or nearly white, 4"-5" long, their pedicels erect; fruiting pedicels and pods erect or in age slightly spreading; pods 2'-4' long, 1/2"-1 1/2" wide, rather blunt; seeds in 2 rows in each cell, winged.

Cliffs and rocky soil, Quebec to Connecticut, Ontario, northern Ohio, Illinois, Michigan, British Columbia, Oregon, south in the Rocky Mountains to Colorado and Utah. May-Aug.

11 Arabis Drumm Ndii A Gray Drum Mond s Rock Cress 42111 Arabis Drumm Ndii A Gray Drum Mond s Rock Cress 422

12. Arabis Brachycarpa (T. & G.) Britton. Purple Rock-Cress

Fig. 2080

Turritis brachycarpa T. & G. Fl. N. A. 1: 79. 1838. A. confinis S. Wats. Proc. Am. Acad. 22: 466. 1887. A. brachycarpa Britton, Mem. Torr. Club 5: 174. 1894.

Biennial, somewhat glaucous, generally purplish, glabrous except at the base, simple or sparingly branched, 1°-3° high. Basal leaves stellate-pubescent, obovate or spatulate, 1' - 3' long, dentate, narrowed into a petiole; stem-leaves sessile, glabrous, auricled at the base, lanceolate or oblong-linear, about 1' long, entire or with a few teeth; pedicels spreading, 3"-5" long in fruit; flowers white or pink, 4" broad; petals twice the length of the calyx; pods narrowly linear, nearly straight, 1'-4 1/2' long, 1" wide or less, spreading or loosely ascending; seeds in 2 rows in each cavity, oblong, wing-margined.

Sandy or rocky soil, Quebec to Manitoba, Assini-boia, Vermont, western New York, Illinois, Minnesota, and in the Rocky Mountains to Colorado. June-July.

13. Arabis Holbočllii Hornem Holboell's Rock-Cress

Fig. 2081

A. Holbocllii Hornem. Fl. Dan. 11: pl 1879 1827. Arabis retrofracta Graham, Edinb Phil Journ.

1829: 344. 1829.

Erect, simple or branching above, 10'-24' high, stellate-pubescent, hirsute or even nearly glabrous. Lower leaves spatulate or oblanceo-late, tufted, petioled, 1/2'-2' long, obtuse, entire or sparingly toothed, more or less long-pubescent and ciliate; stem-leaves sessile, erect, clasping by a narrow auricled base; pedicels slender, reflexed or the upper ascending, 3"-5" long in fruit; flowers purple or whitish, 3"-4" long, becoming pendent; petals twice the length of the calyx; pods linear, 1'-2' long, slightly more than \" wide, at length reflexed; seeds margined, in 2 rows in each cell; style very short or none.

Greenland to Quebec, Lake Superior, Alaska and British Columbia. Summer.

13 Arabis Holbo LLII Hornem Holboell s Rock Cress 42313 Arabis Holbo LLII Hornem Holboell s Rock Cress 424