CRUCIFERjE 19 



Scotland. If the determination was correct, the species 

 would probably owe its presence to garden culture. 



Biplotaxis erucoides, DC. A common weed of dry 

 cultivated ground in the Mediterranean region which 

 has been recorded several times in Britain as a grain- 

 sifting introduction. 



Diplotaxis muralis, DC. Native of dry rocky ground 

 in the Mediterranean area, and possibly on the sea-coast 

 further north. In Britain it is confined to old walls, 

 rubbishy places about towns, and dry cultivated ground. 

 It shows signs of recent and increasing extension, being 

 absent in the older Herbaria, but now becoming ex- 

 ceedingly common along railway embankments and 

 other lines of traffic as far north as Scotland. 



Enarthocarpus lyratus, DC. A weed of cultivated 

 ground in various parts of the Mediterranean area, 

 especially in Greece and Egypt. It has occurred in 

 waste places in a few scattered localities in England, 

 in some at least of which introduced grain was the 

 cause of its appearance. 



Eruca sativa, Mill. A weed of cultivated and waste 

 ground from the Mediterranean area to Turkestan, 

 including the great cornlands of South-Eastern Europe. 

 It is rather frequently recorded in Britain in connection 

 with the siftings of Eastern grain. 



Eruca vesicaria, Cav. This is stated to have been 

 found by Dr. Leitch at Silloth, in the locality which 

 has produced such large numbers of corn-sifting aliens. 



