64 VIII. CKUCIFERiE. 



Style simple, often very short or none ; stigmas 2, erect or divaricate, or 

 united into a single capitate or minute stigma. Ovules 1, 3, or more in eacli 

 cell, horizontal or pendulous from the parietal placenta. Truit a pod, eitlier 

 long and naiTow, and then called a siliqna, or short and broad, called a 

 silicule, usually 2-celled, each cell opening by a 'deciduous valve, leaving per- 

 sistent the thin septum suiTounded by the nerve-like placentas, which foiin a 

 rim called the replum ; exceptionally the pod is 1 -seeded and indchlsccnt, or 

 separating into 2 indehiscent cocci or into 2 or more bead-like articles. 

 Seeds attached in each cell in 2 rows, one proceeding from each edge of the sep- 

 tum, but when each seed is as broad as the cell they overlap each other, so as to 

 appear to be, and to be described as, in a single row ; testa cellular, some- 

 times winged, often exuding when soaked a thick coat of mucilage. Albumen 

 usually none, Embiyo usually curved, the cotyledons plano-convex with the 

 radicle curved against their edge, when they are said to be accumhent, or over 

 the back of one of them, Avhen they are incimibent ; In the latter case they 

 are either flat or more or less folded over the radicle, or condupUcnte, 

 Herbs or rarely undershrubs, withovit milky juice. Hairs simple, stellate or 

 attached by tlic centre. Leaves simple, usually alternate, entire, lobed or 

 pinnately divided, the radical ones often lyrate and the stem ones aurieled. 

 Stipules none. Flowers usually in terminal racemes, which are at Si'^t 

 corymbose but lengthen out as the fruiting advances, and usually without 

 bracts. 



Crucifer<s form a very large Order, dispersed over nearly the whole ghthe, \mi most abun- 

 dant in the temperate and cold regions of the northern hemisphere. They are raro Avithin 

 the tropics, especially iti districts where there are no high mountain-ranges. The Order is 

 one of the most easily recognized by the flowers or fruits, but, to dcU^rmine the genera aaJ 

 species, it is absolutely necessary to have the pod and the seed in a good state. 



Pods linear, at least 4 times as long as broad. 



Forh terete or tetragoiious, the valves turgid or with a verg promi- 

 nent midrib. 

 Seeds in a single row. Pods long. 



Cotyledons accunibent . . • 2. Barbakea. 



Cotyledons incumbent . . * 7. Sisymbhium. 



Seeds in 2 rows. Pods usually short. 



Cotyledons accumbent 1. NastUBTIUM. 



Cotyledons incumbent. 



Petals either obovate or, if narrow, short and erect , , , 8. BlennodU. 

 Petals tapering into a long, subulate, often twisted point . 9. Stknofetalu^ 

 Pods flattened^ usually long, the flat valves parallel with the sep- 

 tum. Cotyledons accumhent. 

 Stem-leaves anricled. 



Seeds smooth -....., 3. Akauis. 



Seeds pitted ♦ , 4, Caupamine. 



Stem-leaves divided or rarely entire, not anricled 4. CardaMTNE. 



Pods short or oblong, rarely 4 times as long as broad. 

 Pods terete or globular^ the valves very convejr. 



Cotyledons accumbent 1. Nasturtiv?^ 



Cotyledons incnmbent. 



rrultiug peduncles recurved, pod ripening undergromid . . 10. Geococcu3, 

 Pruiting racemes erect. 



Petals tapering into a long, subulate, often twisted point . 9. Stexofetat.uM 

 Petals obovate, or if narrow, erect and short. 



Septum broader than the transverse diameter of the pod 8. BlennodI'^- 





