TETRADYNAMIA— SILIQUOSA. Sinapis. 221 



Ait. H. Kew. V. 4. 125. DeCand. Syst. v. 2. 607. Lam. t. 566. 

 Gi;Ertn. t. 143. 

 Sinapi. Tourn. t.l\2. 



Cal. equal, and nearly flat, at the base; leaves oblong, 

 straight, spreading almost horizontally from the very 

 bottom, deciduous. Pet. obovate, rounded, entire, or 

 slightly notched, spreading; claws linear, erect. Filam. 

 awl-shaped, simple, erect. AntJi. oblong, slightly spread- 

 ing. Glands 4 ; 2 at the inside of the shorter filaments, 

 2 at the outside of the longer. Germ, cylindrical, taper- 

 ing into a very short stijle. Stigma capitate, rather small. 

 Pod nearly cylindrical, variously beaked, of 2 concave 

 undulated valves, and 2 longitudinal cells, besides 1 for 

 the most part in the beak, generally barren. Seeds in a 

 single row, nearly globular, with 1 occasionally in the 

 beak ; cotyledons folded, incumbent, their doubled edges 

 meeting the radicle. 



Upright, branching, annual or biennial herbs^ often hairy or 

 bristly. Leaves lyrate, or deeply cut, or toothed. Fl. 

 yellow, in corymbose clusters. Seeds acrid. The beak 

 of the pod, in some, is little else than a permanent unal- 

 tered style. The seeds in those species which constitute 

 DeCandolle's Diplotaxis are partially and very imper- 

 fectly two-ranked, and their calyx spreads much less than 

 it ought to do, this being the chief mai'k of difference 

 between Sinapis and Brassica. 



1. S. arvensis. Wild Mustard. Charlock. 



Pods with many angles, rugged, longer than their own awl- 

 shaped beak. Leaves toothed ; partly lyrate, or hastate. 



S. arvensis. Linn. Sp. PI. 933. fVilld. v. 3. 554. FL Br. /21. 



Engl. Bot. V. 25. t. 1748. Curt. Loud. fasc. 5. t. 47. Hook. 



Scot. 204. DeCand. Syst. r. 2. 615. 

 Sinapi n. 467. Hall. Hist. v. 1. 203. 

 Rapistrum arvorum. Rail Syn. 295. Ger. Em. 233./. Lob. Ic. 



198. f. 

 R. flora luteo. Bauh. Hist. v. 2. 844./. 

 Irion. Fuchs. Hist. 257 . f. Ic. 143. f. 

 Lampsana vera. Dalech. Hist. 542. f. 



In corn fields, a very troublesome weed ; abundant in waste ground 

 newly disturbed. 



Annual. May. 



Root small, tapering, rigid, sometimes a little tuberous, but not 

 caulescent. Stem leafy, striated, often purplish, rough with 

 sharp reflexed bristles. Leaves stalked, rough, variously toothed j 



