24 ALIEN FLORA OF BRITAIN 



Lepidium perfoliatum, L. Appears to be a native of 

 Eastern Europe and Western Asia, where it grows in 

 dry desert regions as well as in cultivated land. It 

 is a characteristic weed of some parts of the grain- 

 producing area of Eastern Europe, to which fact it 

 owes its appearance in England in places where grain- 

 siftings have been thrown. 



Lepidium ruderale, L. A species of wide range, 

 extending completely round the north temperate zone, 

 but almost always in places frequented by man. It may 

 possibly be truly native in Afghanistan, for there is a 

 note by Aitchison in the Kew Herbarium that the species 

 is " abundant in lands from which the river had retired 

 in spring," in the Hari-rud valley. It is common in 

 some parts of South-East England, but only in waste 

 places. 



Lepidium sativum, L. Garden Cress. Said to be 

 indigenous in Persia ; extending to cultivated fields in 

 Eastern Europe and Western Asia, but only found 

 casually near gardens in other parts of Europe, including 

 England. 



Lepidium virginicum, L. This North American weed 

 has been recorded in several localities in England in 

 connection with town rubbish. It is probably sometimes 

 grown in gardens in the place of ordinary cress. 



Lunaria annua, L. A native of woods in Southern 

 Europe. It is a favourite garden plant in England, and 

 occasionally appears in banks and hedges. Its per- 

 sistence in certain localities of this kind has given the 

 impression of its being wild. 



