CRUCIFER/E 



35 



bear thick clusters of yellow flowers. The pods 

 are smooth, hang downwards, and only contain 

 one seed, which is very rich in oil. 



Nasturtium officinale (Watercress), is a common 

 plant in ditches and in shallow water generally, 

 and also at the borders of streams. The stem is 

 rather stout, fleshy, branching, and sometimes 

 creeping ; the flowers are small and white. The 

 pods are about three-quarters of an inch in length, 

 and are arranged in a double row. It is generally 

 only a few inches long, but sometimes grows to 

 a length exceeding 2 feet. It has, however, been 

 introduced into Australia and New Zealand, where 

 it has suddenly begun to grow with such luxuriance 

 that it often reaches a length of 5 or 6 feet, and 

 threatens to block up the rivers. 



The name Nasturtium is often incorrectly 

 applied to a handsome garden flower, also called 

 with equal impropriety "Indian Cress" {Tropceo- 

 lum majus). It really belongs to an exotic Order 

 allied to the Geraniums, called Tropceolacece . It 

 is grown either low or as a creeper ; the leaves are 

 large, very thick, and the whole plant has a strong 



odour resembling that of mustard and cress. It 

 bears large showy red or yellowish flowers (only 

 one on a stalk), yielding large green carpels, which 

 are sometimes pickled. 



Many cruciferous plants are cultivated, but they 

 suffer much from the attacks of various insects, 

 for numerous wild plants belong to this Order, 

 and as the insects which attack them are usually 

 not very particular in their choice of food, they 

 spread and multiply on cultivated plants, to which 

 they often cause serious injury. We have already 

 mentioned the small beetles which are so destruc- 

 tive to Turnips ; but there are many other insects 

 which are almost equally destructive to Cabbages, 

 Turnips, etc. Among these are the caterpillars 

 (mostly green) of no less than five white butter- 

 flies : the Large White (Pieris brassicce), the Small 

 White {P. rapce), the Green-veined White {P. 

 napi), the Bath White {P. daplidice), and the 

 Orange Tip {Euchloe cardamines). The caterpillars 

 of all these butterflies are green, though sometimes 

 inclining to yellowish or bluish. The Large and 

 Small White are almost always common in gardens ; 



