382 



TETRADYXAMIA 8ILIQU03A 



316. ARABI3. L. Mat. Gen. 5fi4. 

 [Etymology obscure; supposed lo have been originally an Arabian gcnuj.1 



Calyx erect. Petals unguiculate ; border spreading, entire, obovate 

 or oblong. Filament9 without teeth. Silique linear, crowned with 

 the subsessile stigmas ; valves flattish, nerved, or veined. Seeds in a 

 single series, oval, or orbicular, compressed, often margined ; cotirt. 

 edons accumbent. 



1. A. hirsuta? Scop. Hirsutcly pubescent ; leaves mostly all den- 

 tate ; radical ones ovate-oblong, or oval, petiolate, cauline ones ovate 

 or lanceolate, sessile, amplexicaul, often sagittate ; siliques numerous! 

 straight, erect. Beck, But. p. 29, 



A. sagittata. Torr. Comp. p. 250. Also ? DC. Prodr. 1./,, 143 

 LindL Ency. p. 540. Beck, L c. Eat. Man. p. 24. 

 Turritis hirsuta 1 JVilUL Sp. 3. p. 543. Pers. Myn. 2. p. 205, Muhl 

 Catal.p. 61. 

 T. ovata. Pursh, Jm. 2. p. 438. 



Hirsute Arabis. 



Root perennial? (biennial, Willd. DC. kc). Stem 6 to 12 or 15 inches hich 

 often branched at base, or several from the root, striate, hairy, hairs simple and 

 branched. Radical leaves half an inch to an inch long, and 1 third of an inch 

 to half an inch wide, varying from roundish-ovate to oval and obovate-oblonsr, ere- 

 nate-dentate, sometimes incised, abruptly contracted to a Hal petiole half an inch 

 to an inch in length; stem-leaves 3 fourths of an inch to 2 inches long, and 1 third 

 to 3 fourths of an inch wide, ovate and ovate-lanceolate, rather acute, serrate-den- 

 tate, sessile, sagittate-cordate at base, and semiamplexicaul. Raceme 2 to 6 inches 

 long; pedicels about half an inch long. Petals ochrolcucous, obovatc-oblone, 

 twice as long as the calyx. Siliques 1 to near 3 inches long, linear, slender, rather 

 erect; valves veined, often (but not constantly) with a keel-like central nerve, 

 yellowish green, smooth and shining; style rather short, clavate. Seats com- 

 pressed, oblong, margined at and near the apex, reddish brown. 



Hab. Brooke's Mill ; Black Rock : not very common. Fl. April-May. Fr. June-July. 

 Obs. Our plant differs considerably from my European specimens of A. hirsw 

 ta— the radical leaves being more abruptly narrow*! at base, the racemes more 

 loose, and the siliques not so strictly erect. It is, however, a variable species; 

 and may perhaps be allowed, with propriety, to comprise all the varieties indict' 

 ted by the synonyms quoted above. Collected near Brooke's Mill, in 1838, by Mr. 

 Joshua Hoopes ; and subsequently at Black Rock, by D. Towksexd, Esq. 



2. A. isvioata, DC. Smooth and glaucous ; radical leaves obo- 

 vate, and oblong, dentate, sub-pctiolate ; stem-leaves lancc-linear, rather 

 obtuse, sessile, amplexicaul, the upper ones entire ; pedicels about as 

 long as the calyx, smooth, erect ; siliques numerous, long, linear, nearly 

 straight, erect, or spreading. Beck, Bot. p. 30. 



Turritis laevigata. Willd. Sp. 3. p. 543. Pers. Syn. 2. p. 205. Jlluhl. 

 Catal.p. 61. Pursh, Jim. 2. p. 438. Mat. Gen. 2. p. 71. Bart. 

 Phil. 2. p. 57. 



Smooth Arabis. 



Root perennial, Muhl. Torr. Beck, biennial, Willd. Pursh, DC. somewhat fu- 

 siform, with coarse fibrous tranches, often oblique, or nearly horizontal, whitish. 



