Cl. 13.] CRUCIFERJE. 139 



mostly terminal, racemose, or corymbose, sometimes 

 panicled." 



This Order, constituting Linnaeus's 15th Class, is 

 so natural in itself, that we can scarcely say whether 

 any real affinity exists between it and any other. Hy- 

 pecottm, in the last, betrays a slight resemblance, rather 

 than a relationship, to this ; as Cleome does in the 

 following ; but this last genus is incorrectly referred 

 by Linnaeus to his Tetradynamia, according to any 

 rule that I can discover. 



The genera of Cruciferte, in which Jussieu follows 

 Linnaeus, are among the least satisfactory in either 

 of their systems. Mr. Brown, in Ait. Hort. Kew., 

 ed. 2. v. 4. has greatly improved them, taking into 

 account the position and direction of their Cotyledons, 

 whether spiral, doubled, or flat; incumbent, folded 

 together upon the Embryo, or accumbent, folded con- 

 trarywise, their edges meeting the Embryo. The num- 

 ber of Seeds also lends occasional assistance, in the 

 Siliculosa at least. 



In some few instances, 2, or even 4, of the Stamens 

 are wanting. 



Crambe, Coronopus, Peltaria, whose Pouch does 

 not burst, Isatis, Vdla y Teesdalia Br., fig. 25-27, 

 Iberis, Thlaspi, fig. 23, 24, Lepidium, Farsetia, and 

 Lunaria, are among the best genera in Tetradynamia 

 Siliculosa ; as are 



Arabis, Brassica, Sinapis and Raphanus in T. Si- 

 liquosa. Mr. Brown's Malcomia appears more satis- 



