60 DISTRIBUTION OF PLANTS 



Ulex europaeus, U. nanus, Cytisus scoparius, Ononis' 

 arvensis, O. spinosa, Genista anglica, Calluna vulgaris, 

 Erica cinerea, E. Tetralix, Rosa arvensis, R. spinosa, 

 Rubus fruticosus, and other varieties or species. Ruscus 

 aculeatus occurs principally in the south of England. 

 Vaccinium Myrtillus is more plentiful in Scotland and 

 the north and west of England. The gravelly commons 

 in the south of England are more frequently covered with 

 the rosaceous and papilionaceous shrubs ; those in the 

 north and west with the Ericinese. In the lower or more 

 southern part of the region, we sometimes find in great 

 plenty various herbaceous species which gradually run 

 out or become rare northwards ; such are Tamus com- 

 munis, Bryonia dioica, Linaria Elatine, Euphorbia exigua, 

 E. amygdaloides, Poa aquatica, Verbena officinalis, Linum 

 angustifolium, Sison Amomum, Antirrhinum Orontium, 

 Cnicus acaulis, Anthemis nobilis, &c. &c. On the other 

 hand, several, that are rare or wanting in the south and 

 south-east of England, decidedly increase in frequency 

 northwards or towards the hilly tracts ; such are Pingui- 

 cula vulgaris, Parnassia palustris, Geranium sylvaticum, 

 Trollius europaeus, Lysimachia nemorum, Carex dioica, 

 Gymnadenia conopsea, Habenaria bifolia, H. viridis, 

 Narthecium ossifragum, and Comarum palustre. Em- 

 petrum nigrum (Sussex), Saxifraga hypnoides (Somerset), 

 and Habenaria albida are very uncommon in the plains, 

 indeed scarcely belonging hereto. 



In the extreme south of England, the orange ripens 

 fruit when trained against walls and with the occasional 

 protection of mats in severe weather. Some varieties of 

 grape ripen yearly against walls in the south of England, 

 and in very favourable seasons almost over the whole 

 region. The walnut, filbert, fig, mulberry, and apricot 

 succeed as standards ; but chiefly in the southern part of 

 the region. The chesnut ripens on the shore of the Firth 

 of Forth (Loudon, Enc. Gard.). The myrtle endures the 



