i6 ALIEN FLORA OF BRITAIN 



Brassica Erucastrmn, L. A native of sandy and rocky 

 ground in Spain, and probably elsewhere in South-West 

 Europe, where it is generally very common on waste 

 ground, and along roadsides. It has been recorded on 

 several occasions in different parts of England under 

 conditions that suggest commercial traffic as the agent of 

 its introduction. 



Brassica hispida, Boiss. A cornfield weed of the 

 Western Mediterranean area which has appeared rarely 

 in England in connection with grain-siftings. 



Brassica juncea, Coss. Largely cultivated in parts 

 of temperate and tropical Asia for the same purpose 

 as B. alba is in Europe. The species has been recorded 

 once or twice in waste places in Britain. It probably 

 reached this country with merchandise from the East. 



Brassica longirostra, Boiss. A Spanish plant once 

 recorded from a railway bank in Warwickshire. 



[Brassica nigra, Koch. Certainly native in Southern 

 England on stream banks. More common as a weed 

 of cultivated and waste ground, and in the north known 

 only in such localities.] 



[Brassica oleracea, L. A native of the southern coasts 

 of England, Wales, and perhaps Ireland, growing as 

 naturally on the cliffs here as it does in the rest of 

 Europe. It is, however, much more common as a relic 

 of cultivation.] 



Brassica Sinapistrum, Boiss. An old-established 

 and abundant weed of cultivated land in Britain as it 



