212 SYSTEMATIC BOTANY. 



Rev. G. Henslow suggests that the original type was not binary or 

 quaternary as generally considered, but quinary, the fifth member of 

 each quincuncially arranged whorl being suppressed. As a rule Crucifers 

 have in the adult condition bractless flowers ; a few species have bracts 

 normally ; and they sometimes occur as abnormalities, and are then placed 

 at the base of the peduncles, or emerge from the side of them, owing to 

 imperfect detachment of bract and pedicel, and consequent uplifting or 

 displacement in course of growth. Subularia has perigynous stamens 

 springing from a cup-shaped receptacle. The fruits of Morisia and Geo- 

 coccus ripen under ground. The long stamens of Atelanthera have 

 1-celled anthers. In Streptanthus, and some species of Ve.Ua, the long 

 stamens are connate in pairs. 



Distribution. This large Order is very natural, and, as usually hap- 

 pens in such cases, the genera are very difficult to deh'ne. The species 

 are most abundant in temperate and cold climates, and seldom found 

 otherwise than on mountains in the tropics. 



Qualities and Uses. The general character is antiscorbutic, the watery 

 juice being often pungent and occasionally acrid. The seeds yield 

 oil, which is contained in their cotyledons. By cultivation the acrid 

 juices become milder, and the structures are easily made very succulent, 

 from abnormal development of parenchyma. Under these conditions they 

 become valuable esculents, either in their roots, as the Turnip (Brassica 

 Jtapa), their stem and leaf-stalks, as Sea-kale (Crambe maritima), their 

 stem, leaves, or undeveloped inflorescence, as Kohl-rabi, Cabbages, 

 Greens, Kales, &c. in all their varieties, and Cauliflower and Broccoli, all 

 apparently derived from Brassica oleracea by cultivation. Brassica 

 Napus, Rape or Colza, is most valuable on account of the oil in its seeds, 

 and its oil-cake as food for cattle. The Swede Turnip is supposed to be 

 a hybrid between B. campestris and B. Rapa or Napus. Radishes (JRa- 

 phanus sativus), Horse-radish (Armoracia rusticana), are cultivated on 

 account of their pungency, as are also the herb and, still more, the seeds 

 of the Mustards, Sinapis alba . and nigra, the latter of which yields the 

 proper table-mustard seed. Water-cress (Nasturtium officinale) and Gar- 

 den-cress (Lepidium sativuni) are pungent salad-plants. Isatis tinctoria 

 and a Chinese species, /. indigotica, yield a blue dye from their silicles. 

 Many of the Cruciferae are remarkable for containing sulphur compounds, 

 both in the seeds and in the herbage, whence the disagreeable smell of 

 water in which they have been boiled, or even of the bruised fresh plant 

 of some, as En/simum Alliaria. Oil of Mustard, obtained by macerating 

 the seeds of Black Mustard in water and distilling, is violently acrid. 

 Many of the genera cited in the list above are represented by common 

 wild plants in this country, the rest are found in most gardens ; Matthiola 

 is the Stock, Cheiranthus Cheiri the Wallflower, &c. 



CAPPARIDACE^E are herbs, shrubs, or rarely trees, with alternate 

 simple or lobed exstipulate leaves ; cruciform flowers ; stamens numerous, 

 or, if 6, not tetradynamous, on a disk, or with an internode separating 

 them from the corolla, and a 1-celled pod or berry with 2 or more parietal 

 placentas ; seeds reniform. aperispermic. Illustrative Genera : Tribe 1. 

 CLEOMEJE. Fruit capsular : Cleome, DC. ; Polanisia, Raf. Tribe 2. 

 CAPPARE^B. Fruit baccate : Cadaba, Forsk. ; Cajjparis, L. 



