THE MIGRATION OF BIRDS. 269 



X X X X X X 



X X 



XXX X X X X 



X X XX X xxxx 



XXX xxxx 



X XX XX xxxx XXvX 



xxx; XX X xxxx xx x '^x x 



X XX XX xxxx XXxX 



X X X ^ XX 



X XXX XX X XX,X..X .X 



XXX XXX ^X X • •• X- XXX 



X XXX XX X XX'X'X "X 



XXX XX 



111 -i .S 1 1 ^-i ?t § I ^ .11 |t§ I ^^t 5 HI 5 



xxxxxxxxx 



