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4< British Birds," is to the effect that when about 600 geographical 

 miles east of Newfoundland, flocks of this species were observed 

 by Dr. Dewar, crossing the Atlantic before a stiff westerly breeze. 

 Many of the flocks alighted on the rigging of the ship, and of 

 these twelve examples were captured. Occurrences of this kind 

 are so common in the North Sea that Professor Newton very 

 reasonably suggests the opinion that many other migrants may 

 have been thus helped across the Atlantic by human aid ; with 

 what success may be inferred from the American element in the 

 list of so-called " British " birds. This does not meet with Herr 

 Gatke's approval, however, who remarks : " We cannot, however, 

 reasonably admit that cases like that just instanced explain the 

 passage of American migrants to Europe generally." He takes it 

 for granted that these flocks of Crossbills undoubtedly reached 

 the coast of Europe in safety long before their imprisoned com- 

 rades. To accomplish this it will be as well to see what feats 

 the former would have to perform. 



Herr Gatke tells us that all migrants start on their journeys 

 with empty stomachs. We may, therefore, reasonably assume 

 that these Crossbills were no exception to the rule. The stretch 

 of ocean between Newfoundland and Ireland covers sixteen 

 hundred geographical miles, with no intermediate resting-place. 

 To cover the distance in the time he assigns as the limit during 

 which a bird can remain on the wing without food and rest, viz., 

 fifteen hours, will require a speed exceeding 100 miles an hour. 

 Now, according to his observations on Heligoland, a stiff westerly 

 breeze would be unfavourable to the performance of migration 

 at low elevations, birds rising to vast heights during the pre- 

 valence of such conditions near the earth. These Crossbills, 

 however, were flying so low that they took advantage of the 

 presence of the ship which afforded them an opportunity for a 

 rest. This species, moreover, is by no means an expert flyer. 

 Does it seem at all probable, therefore, that under the adverse 

 conditions encountered these flocks actually reached the west 

 coast of Ireland in safety ? Could a Crossbill, even under favour- 

 able conditions, fly at the rate of one hundred miles an hour, 

 and maintain this velocity for sixteen hours without a break ? 



Common observation has revealed the fact which is confirmed 



