FEBRUARY 49 



such heavy crops of corn and potatoes, was once part 

 and parcel of the deep fen. Its very level has sunk 

 many feet since the epoch when it was a spongy morass. 

 But picture it as it was, when for league upon league 

 the frozen meres gleamed cold in their setting of hoary 

 reeds all tagged with ice, or later when the green 

 feathered spears rustled and bent before the summer 

 breeze which transformed the dreary waste into a 

 jungle of lush and tall-growing herbage, where, side 

 by side with the loosestrifes purple and yellow, the 

 hemp-agrimony and the meadow-rue, grew rare marsh 

 plants, which drainage has almost banished from our 

 flora. Still, at the end of June, the bulrushes give off 

 their clouds of golden pollen, but, with the disappear- 

 ance of their food plants, some of the insects character- 

 istic of our English Low Countries have become scarce 

 or extinct, a notable example of the latter being the 

 great copper butterfly, formerly the glory of the 

 Whittlesea fens. Happily, we may still, in one locality 

 at least, see the strong- winged swallow-tail dash 

 across the levels or find its larva, in its brilliant livery 

 of clear green with jet-black stripes spotted with orange 

 red, feeding upon the marsh-parsley or fennel. 



But it is in the matter of their bird population that 

 the by-gone glories of the fens contrast most strongly 

 with present-day conditions. Every stage in the 

 reclamation of the drowned levels has still further 

 unfitted them to be the haunt of the great hosts of 



