2 ON THE STRUCTURE OF CRUCIFEROUS FLOWERS. 
interior, or opposed to the axis, the other exterior.* The two 
lateral folioles are inserted a little lower than the interior and ex- 
terior, ( foliola paullo demissius inserta, Endlich). We shall explain 
hereafter the cause of this difference. It is sufficient, at present, 
to say, that in several species this difference is almost null, and 
that botanists in their descriptions have always considered these 
four folióles as forming part of a single whorl. We conclude, then, 
that the first verticillum in the Cruciferæ presents the quaternary 
type. 
The two lateral folioles are often a little broader than the others : 
they present, sometimes, at their base, a slight dilatation, a kind 
of gibbosity (Hesperis, Matthiola), or even a sort of spur (Londraba 
sulphurea, Med.). Notwithstanding this, all writers have described 
the calyx as a regular verticil. 
M. Krause, in some lately published remarks,} affirms that the 
anterior and posterior leaflets, instead of being placed a little lower 
than the two lateral ones, are, in reality, a little higher, and that 
in point of time, they are produced before them in the bud. He 
imagines that the former of these is a bract, and the latter a bracteole. 
M. Duchartre is of a different opinion.t According to him 
the anterior and posterior leaflets are certainly developed first. We 
have ourselves ascertained this precedence, and we have seen, like- 
wise, that their insertion is a little lower than that of the two 
others. As to the names bract and bracteole, given to these organs 
by M. Krause, it will be sufficient to say, that it is not possible 
that there should be a bracteole between a flower and the axis of 
inflorescence. 
COROLLA. 
The BUE is formed of four petals, longer, usually, than the 
calyx, with the folioles of which they alternate. 
This verticil is almost always regular.|| Some Cruciferæ, how- 
.* Sépales distémones ou placentaires. DC, 
+ Einige Bemerk. ueber Blum. der Fumar. und Crucif. in Flor. od, Bot, Zeit. — — 
1846, No. 8 et 9. 
+ Revue Bot. 1846, vol. i. p. 208. 
i The structure of the flower in Cruciferæ is so regular that it has been generally a 
remarked by all observers.— DC. Mém. sur les Crueif?res, 1821, p. 7. 
