80 CRUCIFER^E. Ahabis. 



• Seeds immarginate or slightly margined. 



1. A. alpina (Linn.): stem branching, somewhat diffused, and. with the 

 leaves, clothed with a viDous branched pubescence; leaves many-toothed ; 

 radical ones somewhat petioled ; cauline cordate, clasping,- peduncles nearly 

 glabrous, longer than the calyx. Uook. fl. Bor.-Am. 1. p. 41; Bot. mag. i. 

 226 ; Pursh, fi. 2. p. 436 ; DC. prodr. 1. p. 142. 



Labrador.— A native also of the north of Europe. 



2. A. hirsuta (Scop.): stem erect, ■ toothed or somewhat entire, and, with 

 the stem, hirsute with a branched pubescence; radical ones oblong-ovate, 

 petioled or sessile; cauline ones oblong or lanceolate, somewhat clasping, 

 mostly auricled at the base or sagittate; siliques numerous, erect. — DC. 

 prodr. I. p. 144 ; Hook. ! fl. Bor.-Am. 1. p.A2 ; Cham. ^ Schlecht. in Linnoea, 

 l.p. 15; DarUngt.Jl. Cest. ed. 2. p. 382. A. sagittata, DC prodr. I. p. 143. 

 Turritis hirsuta, Linn. T. oblongata, Bof. 



p. glabrata: whole plant glabrous ; leaves mostly entire. 



y. ovata : radical leaves spatulate, petioled ; cauline ones ovate, parti'/ 

 clasping, not auricled. — A. ovata, Poir. A. sagittata (i. ovata, DC. prodr. I. c. 

 Turritis ovata, Pursh ! fl. 2. p. 438. 



Rocky places, Canada! (lat. 68^) to Virginia ; west to Oregon and Sitcha. 

 /». Oregon, Dr. Scolder ! y. Hoboken, New Jersey [ — (T) Stem about a foot 

 high, often glabrous above. Flowers greenish-white. Silique straight, 1-2 

 inches long, scarcely half a line wide ; stigma nearly sessile. Seeds with a 

 narrow margin. 



3. A. dentata : more or less rough with a stellate pubescence ,■ radical leaves 

 obovate, tapering at the base into a petiole as long as the limb, irregularly 

 dentate with sharp salient teeth ; cauline ones oblong, clasping ; flowers mi- 

 nute ; petals spatulate, scarcely longer than the calyx ; siliques short, spread- 

 ing, on very narrow pedicels, pointed with the nearly sessile stigma ; stem 

 branched from the base. — Sisymbrium dentatum, Torr. J in Shorfs 3rd 

 suppl. cat. pi. Kentucky. 



Sandy banks of the Ohio ! Missouri ! Mississippi ! and Arkansas. April. — 

 @ Plant 1-2 feet high ; the pubes-cence (particularly of the under surface of 

 the leaves) short and rather scabrous. Stem slender, sometimes decumbent 

 at the base. Radical leaves 2i inches long, and three-fourths of an inch 

 broad. Flowers scarcely 2 lines long. Sepals hirsute. Petals dusky white 

 (with a tinge of purple, Nutt.). Anthers ovate-oblong. Silique an inchlong, 

 not a line in breadth ; valves somewhat convex. Seeds slightly margined. 

 Radicle long and slender, distant from the accumbent cotyledons. 



4. A. stricta (Huds.) : radical leaves oblong, attenuate at the base, lyrately 

 pinnatifid, hispid with spreading hairs ; cauline ones kw, lanceolate, some- 

 what attenuate at the base ; petals oblong, erect, obtuse, twice the length of 

 the glabrous calyx ; siliques elongated, erect. Hook. — Pursh, Jl. 2. p. 437 ; 

 Hook.Jl. Bor.-Am. I. p. 42. 



Labrador. — U, A native also of Europe. 



5. A. petrcea (ham.) : stem nearly erect, sometimes branched, glabrous; 

 radical leaves petioled, incised or pinnatifid ; cadine ones oblong-linear, en- 

 tire ; petals obovate, unguiculate ; siliques erect-spreading. — Lam. diet. 1. p. 

 221; DC. prodr. 1. p. 145; Hook. Jl. Bor.-Am. 1. p. 42 (excl. syn.); Cham. 

 ^ Schlecht. in Linmea, 1. p. 15. 



On rocks; Canada to Arctic America, and N. W. Coast. Shore of Lake 

 Superior, Dr. Pitcher I — ^ Stems 3-9 inches high. Cauline leaves few. 

 Flowers white or lilac. Style very short or none. — Habit of Arabis lyrata, 

 from which it differs in its perfectly accumbent cotyledons and perennial 

 root. 



