Class XV. Order II. 249 



Class XV. TETRADYNAMIA. Six stamens, four 



long and two short. 



Order I. S1L1CULOSA. Seeds in a silide. 



264. DRABA. Silicle entire, oval-oblong, the valves 

 flat, parallel to the dissepiment. 



265. LEPIDIU.M. Silicle elliptic, emarginate, the 

 valves carinate, but not margined. 



266. THLAPSI. Silicle inversely heart shaped, the 

 valves carinate and margined. 



267. BUNIAS. Silicle deciduous without opening, 

 somewhat four sided, two of its angles more acute. 



Order II. SlUQUOSA. Seeds in a silique. 



263. ARABIS. Silique compressed. Four nectarife- 

 rous glands like scales, reflected between the leaves of 

 the calyx. 



269. RAPHANUS. Silique cylindrical, swelling at 

 the seeds, somewhat jointed. 



270. CARDAMINE. Silique bursting elastically, the 

 valves revolute, and equal to the partition. 



271. SISYMBRIUM. Silique cylindrical, opening 

 with nearly straight valves ; valves equalling the parti- 

 tion. 



272. ERYSIMUM. Calyx closed ; stigma capitate ; 

 silique columnar, square. 



273. SINAPIS. Calyx spreading; silique cylindri- 

 cal, with the partition longer than the valves. 



274. DENTARIA. Silique opening elastically, the 

 valves revolute ; stigma emarginate ; calyx connivent. 



275. CLEOME. Petals all ascending ; glands three, 

 oue at each sinus of the calyx except the lowest ; germ 

 stipitate ; silique one celled, two valved. 



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