The Swift 

 THE SWIFT 



Cypselus apus (Linnaeus) 



The causes that govern the migratory movements of birds 

 are still unknown. Some species are doubtless impelled by 

 stress of weather or lack of food to seek other quarters, but 

 what power can it be that brings the Swift thousands of 

 miles from another continent to lay its eggs and rear its 

 young, and then precipitately to retire again when the flies 

 on which they feed are most abundant, and the warmest 

 : month of the year has hardly begun ? It is one of the last 

 of the summer birds to arrive, May being generally well 

 ■advanced before we hear its harsh yet pleasant scream of 

 " swee ree," as it swerves in rapid flight round the cottage 

 .or belfry which is to form its summer home. 



This species is the most aerial of all our native birds, and 

 is never seen to settle except when entering the hole under 

 -the eaves where it nests, and, in fact, owing to the length of 

 its wing and shortness of its legs, it cannot raise itself from 

 a level surface should it once settle. 



Gregarious in its habits, it returns yearly to the same 

 place, and, entering through a hole or crevice under the 

 eaves, nests there in security. Swifts, as a family, differ 

 from all other birds in using a sticky, mucous saliva, with 

 -which to bind together rough bits of straw, cobwebs, feathers, 

 etc., which form their nest. The nests of certain foreign 

 species are formed entirely of this saliva, and such nests 

 are eaten with great relish and in large quantities by the 



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