392 FLORA OF CENTRAL NORFOLK. 



and are green during the summer with the wild celery, and 

 gay in the autumn with the marsh mallow. The banks of 

 the Yare, the Waveney, and the Bure, beyond the influence 

 of the salt tides, are composed of marshy ground, in part 

 putting on the appearance of loose bogs interspersed with 

 firm tufts composed of the roots of Carices, rushes and grasses 

 rising at intervals upon them. These are constantly drenched 

 with water, and supported upon a subsoil of silt and turf of 

 twenty feet in thickness. The marshes of Acley and Horn- 

 ing present characteristic specimens. Proceeding upwards 

 along the banks of the rivers, these wet bogs gradually pass 

 into drier and more stable meadows, in which the sedges and 

 rushes are almost banished by the true grasses. 



Some few miles to the north of Norwich is an extent of 

 elevated heath and moor, in which are found the infant 

 sources of the Bure. This tract is considerably higher than 

 the level of the ancient estuaries, and in the summer as- 

 sumes the appearance of a dry heath, yellow in the earlier 

 months with the blossoms of the needle furze, but purple in 

 August with the beautiful Calathian violet, the brilliant field 

 being relieved at intervals by rusty spots of the sun dews, 

 and interrupted occasionally by plantations of young pines, 

 in which a constant war is waged between nature and man, 

 the former in many instances appearing to have almost re- 

 claimed that which had been abstracted from her domains. 

 Throughout the winter these regions are almost entirely in- 

 undated and inaccessible ; and if the adventurous botanist, 

 remembering the summer gambols of the Lacerta agilis, and 

 the treasures which he then reaped from the spot, should be 

 induced to visit them at that period, they will afford to him 

 the three species of Sphagna, and as much depth of the 

 water in which they grow as he may please to wade into. 



The edges of the elevated grounds are still covered in 

 many places by the remains of woods and groves which 

 have served as preserves to many of the species of plants 

 affecting such regions. 



Those districts which have fallen more immediately under 

 the influence of man, and are employed for agricultural pur- 

 poses, occupy all those portions of the chalk slopes and 

 rising grounds which have been reclaimed from either heaths 

 or woods, and of course constitute by far the larger portion 

 of them. In these the native plants have been driven by 

 the operations of husbandry into such corners as are unfitted 

 for their purpose ; the soil is formed by varying admixtures 

 of sand, clay, lime, and the oxide of iron, the sand having 

 been chiefly derived from the beds of crag ; the clay from 



