15^ 



downwards, rather longer than the calyx ; border of each 

 spreading almost horizontally, dilated outward, obtuse, 

 often oblique. 



Nectary of 2 or 4, opposite, mostly dark-green, glands, at 

 the base of the stamens, especially within the 2 shortest, 

 which therefore are curved outwards. 



Stamens 6 ; f laments awl-shaped, erect, shorter than the 

 corolla, in some few instances furnished with a lateral 

 tooth, or an interior scale ; 2 shortest opposite, solitary ; 

 4 longest in opposite pairs. Anthers mosdy erect, oblong. 



Germen superior. Style short, or wanting. Stigma obtuse, 

 various in structure, often much changed after impreg- 

 nation, permanent. 



Pod roundish or oblong, of 2 valves, (rarely jointed and not 

 bursting,) mostly of 2 cells, with a parallel partition, pro- 

 jecting more or less at the summit, the valves separating 

 at their base. 



Seeds roundish, or flattened, on slender stalks, from both 

 sides of the receptacle, which borders the partition. Al- 

 bumen none. Cotyledons 2, either flat or folded, or spi- 

 ral ; either incumbent, lying upon the embryo laterally, 

 or accumbent, their edges at one side meeting the embryo 

 longitudinally. 



These last characters, first noticed by Gaertner, and very 

 easy of detection as soon as the skin of the seed is re- 

 moved, there being no separate albumen, have been found 

 by Mr. Brown to afford the most natural, and indeed 

 absolute, primary characters of these plants. They serve 

 to divide the whole into great natural sections, liable, as 

 far as I can find, to no exception, the genera under each 

 section being easily characterized, and proving much more 

 natural, in habit and fructification, than those formed by 

 Linnaeus, on the nectariferous glands, or other circum- 

 stances. 



The crucifera: are for the most part europsean, generally 

 herbaceous, or, if shrubby, of humble growth. Pubescence 

 either simple, woolly, starry, or wanting. Stem round. 

 Leaves almost always alternate, simple; undivided, or 

 deeply divided, jagged and toothed ; in some few cases 

 compound. PL in clusters, or corymbs, almost invariably 

 destitute of bracteas, mostly white or yellow, sometimes 

 red, seldom blue, or brownish ; often fragrant, especially 

 at night. About 900 species are enumerated by DeCan- 

 dolle, but their number might perhaps be greatly re- 



