MIGRATION 



of them entail flights across wide stretches of 

 open ocean, as in the case of one beautiful little 

 cuckoo (Chalcococcyx lucidus), which summers 

 in New Zealand and Norfolk Island, and winters 

 in Eastern Australia. The distance between 

 New Zealand and Australia direct is about 1,200 

 miles, and there are no resting places en route. 

 The journey may be accomplished via Norfolk 

 and Ivord Howe's Islands by three flights, two 

 of 550 miles and one of 600 miles. Another 

 remarkable feat is that performed by warblers, 

 pipits, shrikes, and sandpipers across the Hima- 

 layas, when travelling to and from Siberian and 

 Central Asiatic summer quarters to Indian winter 

 retreats. These birds traverse a belt of absolute 

 desert of more than a hundred miles in width, 

 having an elevation of over 15,000 feet and inter- 

 sected by numerous snow-capped ridges, the 

 lowest passes of which are, 18,000 feet above sea 

 level." 



Many examples are subsequently given of 

 birds which may be said to deviate from the 

 generally accepted track, and to overcome in 

 their own way the obstacles which are incident 

 to the course chosen. 



Whence and Whither ? 

 In dealing with what may be described as the 

 " whence and whither " aspect of migration, the 

 choice of stations for the purpose of observation 

 is of the first importance. Hitherto much of our 

 knowledge in regard to the bi-annual movements 

 of British birds has been derived from Heligoland — 

 a point in the ocean where many converging fly- 

 lines may be said to meet and cross. In Fair 

 Island Dr. Eagle Clarke may fairly claim to have 

 discovered a second Heligoland, and his seven 



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