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viduals passing across the island to the oyster beds, four miles 

 away, which he estimates at 200 miles an hour is curious. For 

 these latter flights, it will be gathered, are merely undertaken in 

 the daily search for food, and are not portions of a migratory 

 journey. It is a pity that he does not think well to bring forward 

 evidence on behalf of the assertion that birds become the most 

 helpless of creatures as soon as darkness has set in, for observa- 

 tions all point to the contrary being the case. It need perhaps 

 hardly be pointed out that many groups and species of birds 

 become very active in seeking their food at dusk. The Ducks, 

 Herons, Crakes, Eails, Bitterns, Plovers, Nightjars, and others 

 amongst the larger species may be pointed to as instances, and, 

 amongst the smaller are the Common Swift, various Warblers, 

 such as Sedge and Eeed Warblers, Nightingale, and also the Sky- 

 lark. The latter named, however, are not active in search of food 

 after sunset, but are ready at all suitable times during the breeding 

 season to break into song, and, however dark the night, on being 

 disturbed are able quickly and without difficulty to fly to a neigh- 

 bouring haunt, where they are as vociferous as before. 



As an instance of the keenness of sight possessed by Ducks, 

 the writer has witnessed on several occasions, when a flight has, 

 after sunset, visited a small sheet of water, partially frozen over 

 with very thin ice hardly to be distinguished from the open water, 

 that they pitched directly into the latter without the least hesita- 

 tion, the open place, moreover, not being situated in the centre 

 of the pond. 



At the periods of migration, especially in the spring, there is 

 no such thing as really a dark night, and even in the winter, 

 when migration for the most part has ceased, pitch-dark nights 

 are very exceptional, and in the experience of the writer, who 

 does not claim any special gift of sight, it is rarely that the 

 outlines of hills and woods cannot be distinguished at consider- 

 able distances. Coast lines, rivers and sheets of water, of course, 

 will be still more readily discerned. It may be pointed out here 

 that on the approach of cold weather, after a protracted mild 

 spell during the winter, and long after the periods of migration 

 are over, certain species make what may be termed supplemen- 

 tary migrations. These are frequently witnessed at Heligoland, 



