T50 THE MIGRATION OF BIRDS. 



once in the year, either in the Northern Hemisphere 

 or in the Southern Hemisphere ; and the alleged 

 instances of certain northern species breeding in 

 South Africa during their winter sojourn are 

 entirely unsupported by reliable evidence. There 

 is oiie circumstance, however, bearing on this 

 question, to which I should like to call attention, 

 with the view of obtaining more definite inform- 

 ation. Several species of birds known to breed 

 in the high north have often been observed in 

 flocks during summer in that region. Is it fair to 

 presume in every case, as we are apt to do, that 

 these flocks are young non-breeding birds, perhaps 

 born the previous year ? May it not be possible 

 that some of these birds have bred in undiscovered 

 Antarctic breeding-grounds, and are spending the 

 period of the southern winter in corresponding- 

 northern latitudes ? I think more definite inform- 

 ation is required as to these gregarious individuals, 

 seeing that we have some not altogether untrust- 

 wortliy evidence of such thoroughly Polar species 

 as Bonaparte's Sandpiper (Tringa honaparti)^ 

 breeding on the Falkland Islands ; the Eastern 

 Golden Plover {Charadrius fulvus), breeding in 

 New Caledonia (the only records, June and July, 

 of this species at Heligoland are very suggestive) ; 

 and the Turnstone {Strepsihis interpret) ^ breeding 

 on Lord Howe's Island (young partially fledged 

 have been captured in this island) ; whilst the eggs 

 of the Curlew Sandpiper (Tringa sulrirquata), a 

 species that goes as far south as Australia to winter. 



