SIDE lylGHTS ON BIRDS 



It was to this double task, first, of collecting 

 and arranging systematically the facts already 

 known ; and secondly, the discovery of new links 

 which should eventually make the chain com- 

 plete; that Dr. Eagle Clarke addressed himself, 

 with the result that the labours of 32 years are 

 now embodied in the two volumes, ' ' Studies in 

 Bird Migration." It would be clearly impossible, 

 even in the most cursory fashion, to follow the 

 author as he tracks with infinite patience, bird 

 after bird from its birth-place to the land of its 

 winter sojourn, marking its line of flight, and 

 showing the well-nigh innumerable deviations 

 caused by varying climatic and other conditions. 

 To do this, indeed would be to recapitulate a 

 work, which is already in itself a most concise 

 summary of the information achieved. The 

 utmost, indeed, that space allows, is a setting 

 forth of the more prominent of the conclusions. 



In the first place, it is shown that birds when 

 journeying between their more or less widely 

 separated homes, do not, as it is generally sup- 

 posed, move indiscriminately southwards in the 

 autumn, and m like manner northwards in the 

 spring. Each individual migrant of mature 

 age has its accustomed summer and winter 

 quarters, and follows particular and more or less 

 devious routes to reach them. 



There appear, indeed to be highway roads 

 through the air, with certain spots beneath which 

 are known to the main body of travellers as 

 stations for rest and recovery, but there are also 

 innumerable by-ways, which for many reasons, 

 some of which are still obscure, are constantly 

 resorted to. 



" The journeys of many" (Dr. Eagle Clarke 

 writes) " are marvellous performances. Some 



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