SYNOPSIS OF THE GENERA. 



dorsal rib. Sligma of two recurved lobes. Calyx erect, 

 with the opposite pieces swollen at the base. Seeds ovate, 

 compressed. Cotyledons accumbent. 



19. Barbare'a, [Page 901 ] Si/Z^'wa linear, round, the valves 



with a prominent longitudinal rib or vein. Calyx erect, 

 equal at the base. Sligma obtuse, entire, or emarginate. 

 Cotyledons accumbent. 



20. Ara'bis, [Page 902.] .S'lV/^'Ma linear, t?a/i;^s flat, or convex, 



with a longitudinal rib or vein. Calyx erect. Stigma 

 obtuse, entire, or sub-emarginate. Seeds oval or orbicular, 

 compressed. Cotyledons accumbent. 



21. TuRRi'Tis, [Page 905.] Siliqua linear, with ribbed or 



keeled valves. Stigma obtuse, entire, or slightly emar- 

 ginated. Seeds in a double row. Cotyledons accumbent. 

 b. Cotyledons flat, accumbent. Oil 



22. Sisym'brium, [Page 906.] Siliqua linear, round, or 



angular, valves with three longitudinal ribs. Stigma ob- 

 tuse, entire, or emarginate. Calyx equal at the base. 

 Seeds ovate, or oblong. Cotyledons flat, incumbent. 



23. Erts'imum, [Page 909.] Siligua linear, quadrangular. 



Stigma obtuse, entire, or emarginate. Calyx erect. 

 Seeds with flat oblong incumbent cotyledons. 



c. Cotyledons incumbent, deeply channeled, or condu- 

 plicate. O^ 



24. Bras'sica, [Page 910.] Siliqua linear, or oblong, with 



convex valves, having a longitudinal dorsal rib, and some- 

 times with lateral branched veins. Calyx erect. Seeds 

 globose. Cotyledons incumbent, channeled, conduplicate. 



25. Sina'pis, [Page 916.] Siliqua linear, or oblong, with 



couvex valves, having three or five longitudinal ribs. 

 Ca/?/a; spreading. Seeds ^dbose. Cotyledons incumhent, 

 channeled, conduplicate. 



26. DiPLOTAx'is, [Page 920.] Si/z^'Ma linear, or linear lanceo- 



late, valves convex, with a longitudinal rib. Calyx 

 spreading. Seeds ovate, or oblong, compressed. Coty- 

 ledons incumbent, channeled, conduplicate. 



*-^ Valves ivithout ribs, or only slightly ribbed at the base. 



27. Denta'ria, [Page 921.] Siliqua linear lanceolate, valves 



flat, ribless. Seeds ovate, attached by a dilated cord. 

 Cotyledons accumbent. Q— 



