229 



return regularly about sundown every evening from 

 their particular and often far-distant feeding-grounds. 

 These sleeping-sites, which are used from j^earto year 

 and are therefore most prominent objects against the 

 otherwise uniform dull-green of the mangroves, are 

 probably selected by their tenants as the spots most 

 sheltered from the force of the tornadoes, which dur- 

 ing the rains drive down the river with force enough 

 to dasli a ship ashore or overturn a house, much less 

 carry away to destruction any bird which may have 

 been foolish enough to choose an exposed perch. 



Sooner or later an end comes to all things, and 

 eventually the last of the mangroves, which gradually 

 thin out as the water gets less and less brackish, are 

 left behind even by a sailing-boat, and the banks 

 become more diversified and more interesting. They 

 are now low and swampy, and in most places clothed 

 with different species of palms, thorn-bushes and 

 other shrubby growth, mostly covered with a dense 

 tangle of creepers forming an all but impenetrable 

 barrier between the water and the land, above which 

 here and there tower larger trees — here a mighty 

 African mahogany, here a grotesque monkeybread, 

 there again a white-barked silk-cotton tree or group 

 of slender cocoa-nut palms. At intervals a break in 

 this mass of vegetation allows a view of the riverside 

 swamp covered with reeds and long grass, stretching 

 away a waving sea of green this season (November) 

 to the more solid higher ground at some distance from 

 the river-bank. 



Here as the boat drifts slowly along, nearly the 

 whole of the Gambian avifauna — an avifauna 

 essentially that of a river and its immediate surround- 



