42 THE ZOOLOGIST. 



width of two miles, sometimes diminishing to a narrow strip, 

 which, except upon rare occasions, are only disturbed by sheep 

 and cattle, and those who tend them. 



The preservation of Hares in this district for purposes of 

 coursing also has a decidedly beneficial effect so far as the birds 

 are concerned. The owners of the land are all animated by the 

 desire to keep a quiet sanctuary for the multiplication of these 

 rodents. Trespassers are therefore warned off, and so a place 

 of refuge is given for many birds during the spring and the 

 summer months. 



I make no apology for attempting first of all a short descrip- 

 tion of this marsh-land, because physical geography must, or 

 should, always be one of the foremost considerations of a field 

 naturalist, whatever class of life he may be observing, deter- 

 mining as it often does the species he is likely to meet. In the 

 present case the extent and area of the waters of the marsh-land, 

 the amount of cover afforded by aquatic and other vegetation, 

 the denseness of human habitations, or the nearness of factories 

 and towns, are the determining factors of the ornithological fauna 

 of the district. 



In order to appreciate the present features of the country it 

 is worth while to attempt to consider its condition before the 

 river-walls were thrown up, and when it was still subject to the 

 encroachment of every tide. The saltings yet unenclosed give 

 one the opportunity of doing this. In them you have some 

 large stretches of land that have evidently been formed by the 

 deposits of the rivers which run through them. They are, 

 practically speaking, level, but much cut up by large creeks and 

 lesser natural gutters and runnels. By supposing such a tract 

 to be enclosed by a wall so that the sea could no longer flow over 

 it, you might then surmise how the marsh has come to its pre- 

 sent state. The large tidal creeks, some of which are fifty yards 

 or more across, have formed in the process of time what are 

 locally termed "fleets " — large winding lagoons bordered now at 

 the edges by reeds, bulrushes, sedges, and other vegetable 

 growth. Many of the smaller runnels of the one-time salting 

 have become filled up, and present at the present day winding 

 hollows in the otherwise flat meadow-land, filled only after heavy 

 rains. Others of the small creeks have been kept open by 



