CRUCIFERAE 239 



Plate 64. 



A. Brachycarpaea variant DC. I. Small piece of flowering plant. 2. Silicula, 

 containing one seed in each compartment. 



B. Heliophila pilosa Lam., with bee. Medium sized plant. 2. Ripe fruit (siliqua) 

 of H. callosa. 3. Seed, long, section. 3/1. c. Cotyledons, r. Radicle. 



C. Heliophila pusilla L. fil. Nat. size. 



D. Nasturtium officinale L. Water cress. 1. Flowering plant. 2. Flower, one 

 sepal and two petals removed. 6/1. 3. Flower in long, section, without sepals and 

 petals. 8/1. g. Nectariferous gland. 4. Seed, long, section. 8/1. 



Brachycarpaea. 

 This genus consists of two species only, both confined to the western 

 districts, where quite a number of Cruciferae are endemic. Brachycarpaea 

 varians is a compact showy half-shrub, one or two feet high, often quite 

 covered with its pale or deep lilac-coloured flowers. 



Heliophila. 



This is the largest S. A. genus of the family, containing over 60 species, 

 most of them possessing light blue or white, very fugacious flowers. Some 

 species are annuals, others perennials and some half-shrubby. The tiny 

 H. pusilla is as common on fallow grain lands or in the open veld as in Europe 

 the ubiquitous Erophila verna (Whitlow grass). The shape of the fruit 

 varies considerably within the genus (see Figs. B and C). 



One half-shrubby species, H. scandens, is a climber which sometimes 

 covers bushes and hedges with its white flowers. (Natal.) 



Nasturtium. 



The name Nasturtium is unfortunately often employed for a very different 

 plant, viz. Tropaeolum majus, a much favoured garden flower, which is cultivated 

 in many varieties. This, however, belongs to Tropaeolaceae, which are 

 nearly allied to Geraniaceae and the sorrels. The mistake has probably arisen 

 from the similarity of their vernacular names, the 'Tropaeolum being sometimes 

 called "Indian cress" or " cresse des capucins." 



Nasturtium officinale {Water cress, waterkers). This herb is now at 

 home in all temperate regions, having been spread partly by human agency 

 and partly by migratory birds, especially water fowl, which transport the seeds 

 of water plants with the mud that adheres to their feet and feathers. 



To those who like water cress a word of warning may not be out of place, 

 for if any contaminated water should find its way into the pond that supplies 

 the herb, the germs of disease may easily be brought into the house of the 

 unsuspecting buyer. No water cress should be used the origin of which is 

 not above suspicion. 



It is interesting to note how the plant has been modified since its 

 introduction into South Africa, for while it possesses a strong taste, almost as 

 sharp as mustard seed, when growing wild in Europe, e.g. in the Black Forest, 

 it is quite mild here. 



M. 3I 



