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birds lingering at such an uninviting spot — especially uninviting 

 in the spring — unless their need for food 'or rest were very urgent. 

 But in other localities the observations of naturalists point to 

 quite a different conclusion. In our own country, for instance, 

 at various points on the east coast, certain species make their 

 appearance with great regularity at particular times, and so far 

 from evincing any of this unrest and impelling haste, are content 

 to linger for days together before further continuing their 

 journeys. 



The Fieldfare may be singled out as a species illustrating this 

 fact ; even those flocks which pass through the Midlands at so late 

 a period in the spring as the first week in May, so far from 

 exhibiting any of this restless haste, may be seen lingering in the 

 same fields for several days at a time, instead of at once passing 

 on. The case of the Dotterel — a species breeding in the far north 

 of the Palaearctic region — too, is similar, flocks of which are known 

 to tarry in certain districts, not for days, but for whole weeks 

 together. Again, at Gibraltar, Col. Irby as early as March 11th 

 met with very large numbers of the Common Crane migrating due 

 north. In the course of a single hour he calculates that at least 

 four thousand must have passed by. As the Crane breeds only 

 very locally and very sparingly in Spain, there can be no doubt 

 that these flocks were en route to the north of Europe. But at 

 this period their breeding grounds would not be fit for habitation. 

 No doubt the journey would therefore be broken at some convenient 

 locality in Western Europe. To the writer the very fact of so vast 

 a number of birds visiting a little spot like the island which Herr 

 Gatke describes as a most unattractive residence for birds, points 

 to the probability that the greater number — certainly of the smaller 

 birds, if not the larger — also conduct their migrations in compara- 

 tively short stages. The fact of the greatest number calling during 

 periods which we are told are the most favourable to an unbroken 

 flight — viz., the prevalence of warm weather with light south- 

 east winds — seems to lend additional force to this conclusion. 

 The central position alone of Heligoland does not afford satis- 

 factory proof that this is the true reason why the island is so 

 exceptionally favoured as a place of call by so many species. 

 For, on Herr Gatke 's theory of migration, conducted in a broad 



