554 ANNUAL, EEPORT SMITHSONIAN INSTITUTION, 1910. 



tinent at Labrador and Nova Scotia, and under ordinary circum- 

 stances makes no landfall till it strikes the Guiana coast, a distance 

 of about 2,000 miles. It is perhaps more remarkable that instead of 

 returning in spring to its breeding grounds by the same route it 

 takes in fall to its winter quarters, it follows an all land route and 

 traverses the length of two continents, thus furnishing* the most 

 extraordinary migration route of any existing bird, as pointed out 

 by Prof. Cooke. 



An attempt to apply to the case of the Pacific plover wintering in 

 HaAvaii the same principles so well worked out for the Atlantic coast 

 form is not so successful. About September the wind that prevails 

 in the north Pacific immediately south of the Aleutians is from the 

 northwest. It is generally believed that migrating birds prefer to 

 fly on a beam wind. Ity heading southwest birds migrating to Ha- 

 waii might have the northwest wind abeam till about the neighbor- 

 hood of latitude 30°, where they would be almost sure to pick up the 

 northeast trades. By then changing their course to southeast they 

 would be enabled to fly with wind abeam till they sighted the islands. 

 That they follow such a course in fall and steer their way by either 

 the northwest wind or the northeast trades there is not a particle of 

 evidence that I can bring forward, nor do I know any facts to justify 

 a statement that they do or do not utilize the winds as guides either 

 in fall or in spring. 



The results of recent experiments by Prof. John B. Watson with 

 sooty and noddy terns along our south Atlantic coast go far to prove 

 the contention long maintained by many that birds actually possess a 

 sense of direction tantamount to a sixth sense. If we grant this, as 

 we may ultimately be compelled to do, the ability of birds to find 

 their way both by land and sea is explained without further trouble 

 and quite independently of landmarks of any kind or of the winds. 

 The possession of such a useful sense will explain many difficult prob- 

 lems of migration, and among others the apparent confidence with 

 which migrants boldty launch out from Hawaii for a 2,000-mile 

 flight across the Pacific, without the aid of any compass apparent to 

 human intelligence. 



Danger of oceanic migration. — Of the fall migration of the golden 

 plover on the xVtlantic it ma}' be remarked that, while the birds have 

 no landmarks to steer by after leaving the northeast coast, they are 

 yet within comparatively easy flight of the mainland, and in event of 

 an unfavorable northeastern wind they can, and in fact often do, 

 take refuge on the New England coast; and farther on, in bad 

 Aveather or in case of unpropitious winds, they alight for rest and 

 food in the West Indies. 



The Pacific ploA-er traA T erses a much more hazardous route, since, 

 when once clear of the Aleutian Islands, it not only leaves all land- 



