THE SWALLOWS 



The Swallows comprise a homogeneous group or 

 family, and one that so far as is at present known is 

 not very closely allied to any other assemblage of 

 birds. Their homogeneity is asserted not only by 

 peculiarities in their pterylosis (or the pattern in 

 which the feathers are arranged on the body), but 

 by their wide flat bill, small legs and feet, and 

 long pointed wings containing nine primaries only, 

 which are further characterized by the tertials not 

 reaching beyond the middle of the wing. There 

 are upwards of a hundred species in the present 

 family. The Swallows are unquestionably an Inter- 

 Tropical group, extending chiefly as migrants into 

 the more temperate regions of both northern and 

 southern hemispheres. The Swallows, although not 

 generally speaking a brilliantly coloured group, are 

 somewhat showy, the plumage of many species 

 glowing with metallic sheen, whilst others are remark- 

 ably beautiful. These birds are songsters of very 

 unequal merit, some species being poor vocalists, 

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