192 OUR GREATEST TRAVELERS 
“April, 30 
\ April, 20 
Ba {3 April 10 
March,| 
February20} 
: f be March, 30 
f =f i 
40 er ‘March,20 rf 
ra) 
es Mare 
& March, | 
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120° 110° 100° 
THE ROBIN MOVES MUCH QUICKER ON THE PACIFIC THAN ON THE ATLANTIC 
The dotted lines connect the places at which the robins arrive simultaneously, The heavy 
solid line marks the division between the eastern and the western forms. The heavy dotted 
line represents the migration route of the Alaska breeding birds (see pages 190 and 193). 
