390 FLORA OF CENTRAL. NORFOLK. 



Art. III.— The Flora of Central Norfolk. By Mr. R. J. Mann. 



The county of Norfolk is, to the British naturalist, a field 

 of abundant interest, in consequence of its forming one of 

 the extremes of his native regions, in which the ocean marks 

 out a defined boundary to the productions of the land, and 

 changes, by its magic touch, the gaudy flower and waning 

 grass into the green sea- weed. The botanic wealth of the 

 most eastern point of England has been well displayed, in 

 an admirable sketch of the natural history of Yarmouth, by 

 the Messrs. C. and J. Paget. The present paper is an at- 

 tempt to supply the next link in the chain of gradation, 

 which terminates only at the shores of Sutherland. It em- 

 braces all those localities which fall within the reach of an 

 ordinary day's march of the working naturalist from the 

 vital centre of the district, the city of Norwich. 



The substratum of Norfolk is identical with the great 

 chalk formation of Europe, and its outcross constitutes the 

 greater portion of the high ground of the county ; its edge 

 is marked by a straight line, a little inclined from the north 

 and south direction, and upon the central portion of this 

 edge is built the ancient city of Norwich. The eastern in- 

 clination of the cretaceous mass is covered by a series of 

 beds composed chiefly of sand and loose ferruginous sand- 

 stones, mixed with gravel containing abundance of organic 

 remains, whose characters distinctly register their ocean 

 birth. These marine sandstones, known technically as the 

 Norfolk crag, occupy upon the surface a broad band running 

 parallel to the boundary of the chalk, and not frequently 

 raised to more than a few feet of elevation above the level of 

 the sea. The space intervening between this tract and the 

 German Ocean is partially occupied by irregular masses of 

 gravel and clay, formed by the action of water upon the 

 older rocks of the more western counties, and swept thence 

 by diluvial currents to their present localities, leaving marks 

 of their progress at various stages of their course ; at the 

 same period that these waters were deluging the land, the 

 then surface was channeled by some disturbing force into a 

 series of valleys running more or less eastward, and uniting 

 in that direction in a common termination. The next epoch 

 in the history of these valleys must have presented them as 

 estuaries of the German Ocean, their lower level being of 

 necessity overflowed by its waters. In this state they appear 

 to have remained until about the period of the Norman Con- 

 quest, when, from some uncertain cause or causes, the sea 

 retreated to about its present bounds, and the bottoms of the 



