SECRETS OF ANIMAL LIFE 



HOMING OF SEA-SWALLOWS 



HOMING pigeons have been used by man for 

 more than two thousand years, and still we 

 have no satisfactory theory of their usually success- 

 ful return from great distances to their cots. Still 

 less can we explain the well-authenticated fact that 

 a swallow may return from its wintering in the south 

 to the Scottish farm-steading where it was born 

 the year before. The problem of .homing bristles 

 with difficulties, and it is therefore with eagerness 

 that we turn to a record of the experiments l which 

 have been recently made on the sea-swallows at 

 the Tortugas by Professor J. B. Watson and Dr. K. 

 S. Lashley. The birds were the Noddy Tern and 

 the Sooty Tern, which breed in tens of thousands 

 upon Bird Key. That island of the Tortugas group 

 was surely predestined for the experiments in 

 question, for it is the northern limit of the migration 

 of these two tropical terns, so that if the birds are 

 taken anywhere to the north they will find them- 



1 Papers from the Department of Marine Zoology, Carnegie 

 Institution, Washington, vii. (1915) pp. 1-104, 7 pis. 9 figs. 



1 



