THE SWALLOW 



building or tree. The Swallow becomes increasingly 

 interesting in autumn, when its gregarious instincts are 

 most developed. Many pass the Metropolis on migra- 

 tion. 



The adult Swallow, readily distinguished from the 

 Swift and the two species of British Martins by its uniform 

 steel-blue upper parts and long, slender outermost tail- 

 feathers, has the forehead and throat chestnut, the upper 

 parts and a broad pectoral band blue shot with purple ; 

 the wings and tail are black shot with green, the latter 

 long and acutely forked ; across the tail is a row of circular 

 white spots ; the under parts are white slightly suffused 

 with buff. Bill black ; tarsi and toes black ; irides brown. 

 Length 8- inches (of which the long slender outermost 

 tail-feathers measure nearly 5 inches). The nestling has 

 the chestnut paler, the white spots on the tail pale chest- 

 nut, and the outermost feathers are much shorter. 



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