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INFLUENCES OF CULTIVATION 



was much reduced in size and not a single Water-flea could be 

 found. If a reduction in level has so marked results, what 

 must have been the effect on the myriads of smaller in- 

 habitants of the waters of the draining of hundreds of 

 square miles of swamp ? 



Remembering those transformations of swamp into dry 

 land which have taken place over the whole country, we can 

 easily understand how creatures whose sustenance depends 

 upon the waters, such as the birds of the fens, have fallen 



Fig. 64. Bittern banished from Scotland with the marshes. nat. size. 



off in numbers or have forsaken our land. Consider the cases 

 of two marsh birds which played an important part in our 

 predecessors' dietary, the Bittern and the Crane. 



The former abundance of the BITTERN (Botaurus stellaris] 

 (Fig. 64) in the fens of England, where Bittern-fowling was 

 long a favourite sport, itself would suggest that the "bittour" 

 which "bumbleth in the mire" must have bred in the marshes 

 of the northern kingdom. Fortunately there is stronger 

 testimony of its Scottish domicile, for it is clear from a law 



