ORDER XIII.— CRUCIFER.E. 223 



Order XIIL— CRUCIF'ERJE. (Mustard Family) 



Sepals 4, deciduous, cruciate ; (estivation generally imbri- 

 cate. Petals 4, cruciate, alternating with the sepals. Stamens 

 6, tetradynamous ; the two shorter lateral, occasionally toothed, 

 inserted lower than the others. Disk often with small green 

 glands inserted between the petals and the stamens and ovari- 

 um. Ovary 1-celled, consisting of two carpels, with two pari- 

 etal placenta', which are reflected into the cavity, where they 

 unite and form a false dissepiment. Stigma opposite the dis- 

 sepiments (a remarkable variation.) Fruit a silique or silicle, 

 2-celled, produced by the spurious dissepiment mentioned 

 above ; one or many seeded. Seeds campylotropous, attached 

 in a single row to each side of the placentae. Herbaceous 

 plants, with a watery and generally with an acrid juice, form- 

 ing Class XIV. of the Linnasan system. 



ANALYSIS. 



1. Fruit linear, a silique 2 



Fruit nearly as broad as long, a silicle 8 



2. Seeds arranged in two rows in each cell Nasturtium, 1 



Seeds in one row in each cell 3 



que 4-cornered Erysimum, 7 



Silique terete or flat 4 



4. Flowers purple or pink Warea, 8 



Flowers white 5 



Flowers yellow 7 



5. Silique lanceolate, flowers in terminal racemes Dentaria, 4 



Silique linear 6 



6. Silique curved, long Arabia, 2 



Silique straight, flowers small Cardamine, 3 



7. Silique terete, tapering, appressed to the stem Sisymbrium,, 



Sili<]ue oblong, linear, compressed, few-seeded Leavenworthia, 5 



Silique ensiibrm, or nearly terete Sinapis, 10 



8. Silicle oval oblong Draba, 12 



le reniform Coronopus, 13 



SiHcIe cmarginate Cagsella, 15 



ic cordate Lepidium, 14 



Silicic 2-jointed, somewhat 4-angled Cakile, 16 



Genus L— NASTURTIUM. R. Br. 14—2. (Cresses.) 

 (From the Latin nasus tortus, convulsed nose, from its pungent qualities.) 



Silique nearly terete, sometimes resembling a silicle, usually 

 curved. Stigma 2-lobed. Sepals spreading. Seeds arranged 

 in two series, minute, destitute of margins. Found in wet 



1. N. oFKirixA'LE, (Brown.) Leaves pinnately divided ; a ■ 

 orate, Bub-eordate, repand. Petals longer than tin; calyx. — V. 

 Introdu 



2. X. tanacetifo'lium, (Hook.) Stem much branched, diffuse. Leaves 

 pinnately divided, lobes sinuate or toothed, obtuse, smooth. Flowers 



