240 



Fam. 33. Cruciferae. 



(Plate 64.) 



Herbs or small half-shrubs with alternate leaves and 

 racemose flowers. Flowers bisexual. Sepals 4. Petals 4, 

 cruciate. Stamens 6, rarely less, tetrad y namous, the 



2 lateral shorter, the anterior and posterior pairs longer. 

 Ovary usually biloeular with parietal placentae, which, by 

 meeting in the centre, form a false dissepiment. Fruit 

 usually biloeular, dehiscing by 2 valves from below 

 upwards, rarely i-celled and indehiscent. Seeds pen- 

 dulous, numerous, or rarely solitary ; albumen o. 



About 1200 species in the temperate and colder 



regions. Mostly annual or biennial herbs, ^ ^ 



but in the largest S. A. genus, viz. t /e£ ( ?S\\ 

 Heliophila, a number of perennial, half- | 'ft cf/ffli3k\j i 

 shrubby species occur. 



The number of useful plants of this 

 family is very considerable. Cabbage, Fig. 107. Heliophila 



■>. n ^. 1 111111' pi/osa I. am. Di.i- 



cauhnower, Brussels sprouts, kale, kohlrabi, gram . ,,. Nectar- 

 turnips, rape, mustard and radish are some ,fcrous 6 Iand - 

 of the most commonly cultivated kinds, while stocks 

 and wallflowers are not less favoured garden plants. 

 Some annuals are troublesome weeds, like Rap/ianus 

 Raphanistriwi (charlock, ramanas) which invades grain lands, 

 and the shepherd's purse in gardens (herderstasje). 



Of South African species none are of special value for 

 domestic use, but quite a number deserve more attention 

 on account of their deep blue or purplish flowers. 



It is remarkable that the western coast districts 

 possess several monotypic and endemic genera, viz. Chamira^ 

 Cycloptychis, Palmstruckia, Schlechteria and Carponema. 



The characters for the subdivision of the family taken 

 from the seeds afford good means of classification, but the 

 arrangement according to the shape of the fruit is more 

 convenient, although this separates allied genera and splits 

 even a genus (Heliophilci). For the convenience of the 

 student we give both lists. 



