156 SALMONIA. 



smaller sea insects, he is sure to find his 

 food in the spray of a heavy wave and you 

 may see him flitting above the edge of the 

 highest surge. I believe that the reason of 

 this migration of sea gulls, and other sea 

 birds, to the land, is their security of finding 

 food ; and they may be observed, at this 

 time, feeding greedily on the earth worms 

 and larvae, driven out of the ground by 

 severe floods: and the fish, on which they 

 prey in fine weather in the sea, leave the 

 surface and go deeper in storms. The 

 search after food, as we agreed on a former 

 occasion, is the principal cause why animals 

 change their places. The different tribes 

 of the wading birds always migrate when 

 rain is about to take place ; and I remember 

 once, in Italy, having been long waiting, in 

 the end of March, for the arrival of the 

 double snipe in the Campagna of Rome, a 

 great flight appeared on the 3d of April, 

 and the day after heavy rain sat in, which 

 greatly interfered with my sport. The 

 vulture, upon the same principle, follows 

 armies; and I have no doubt that the augury 



