XrV. CEUCIFEE^. 229 



dons mcumbent, straight or coiled, or transversely folded. ScMzopetalum, Helens, 

 Malcolmia, Streptoloma, Sisymbrium, Gonringia, Erysimum, Heliophila, &c. 



Teibb IV. Camblinb^. — Siliqna short or long, oblong, ovoid or globular. Seeds 

 2-seriate. Cotyledons incumbent. Stenopetalum,, Braya, Camelina, Tetrapoma, 

 Subularia, &c. 



Teibe V. Bkassicb^. — Siliqua short or long, dehiscent throughout its length, 

 or at the top only. Cotyledons folded longitudinally. Brassica, Sinapis, Erucas- 

 trum, Hirschfeldia, Diplotaxis, Eruea, MoHcandia, Vella, Garrichtera, Succovia, &c. 



Series B.-^Siliqua short, dehiscent throughout its length. Valves continuous 

 within, very concave, compressed in a direction perpendicular to the plane of the 

 septum. Septum usually very narrow. 



Teibb VI. Lepidine^. — Cotyledons incumbent, straight or bent, , or condupli- 

 cate longitudinally, or coiled upon themselves. Gapsella, Senebiera, Lepidium, 

 JEthionema, Campyloptera, &c. 



TjiiBE VII. Thlaspide^. — Cotyledons accumbent, straight. Gremolohus, Bis- 

 cutella, Megacarpwa, Thlaspi, Iberis, Teesdalia, Hutchinsia, Iheridelta, &c. 



Series C. - Siliqua short (rarely long), indehiscent, not jointed, often crustaceous 

 or bpny, 1-celled, 1- (rarely 2-) seeded, or 2-4-celled with parallel 1-seeded cells. 

 Pedicels often very slender, drooping in fruit. Seed often furnished with a thin 

 albumen ; testa not mucilaginous. 



Teibb VIII. IsATiDBiE. — Characters of the series. Peltaria, Glypeola, Isatis, 

 Tauscheria, Neslia, Galepina, Myagrum, EucUdium, Bunias, Zilla, &c. 



Series D. — Siliqua transversely 2-jointed, short or long ; lower joint indehiscent, 

 emptj or longitudinally 2-celled, 2-oo-seeded; upper joint indehiscent, 1-celled, 

 1-seeded, or 2- co-celled, with parallel or superimposed cellules. — Siliqua always 

 upright or nearly so, pedicel straight. 



Tkibe IX. Cakiline^. — ^Characters of the series. Gramhe, Muricaria, Bapis-r 

 trum, Gahile, Enarthrocarpus, Erucaria, Morisia, &c. 



Series E. — Siliqua long, not jointed, indehiscent, cylindric or moniliform, 1- 

 celled, manj-seeded, or with several 1-2-seriate, 1-seeded cellules, separating when 

 ripe. 



Tkibe X. EAPHANEiE. — Characters of the series. Raphanus, B'O-ffenaldia, 



Anchoniuw,, Parlatoria, &c. 



« 



A Cruciferous flower is not strictly symmetrical in relation to the floral axis. The arrangement of 

 th« caljx and corolla at first appears to follow the quaternary type,' four sepals alternating with four 

 petals ; but the slightest examination shows that the two antero-posterior sepaM are inserted lower than 

 the two lateral ; the petals, however, evi-dently form a single whorl. The exceptional structure of the 

 androecium has given rise- to many contradictory theories. The two lateral stamens are shorter and lower 

 than the other four, which are in pairs, and alternate with the two lateral./ It is these two pairs of long- 

 stamens which have especially exercised the sagacity of botanists. De CandoUe, and after him Seringe, 

 Saint-Hilaire, Moquin-Tandon, and Webb, admit the quaternary type for the calyx aud corolla, and 

 extend it equally to the androecium, where, according to them, each pair of lond stamens represents a 



