SAND-MARTIN ::i7 



into their nesting-holes/ If these are over water they are better 

 protected from such visitors, hut, on the other hand, are occasionally 

 liahle to be flooded. AM is the case with their congeners, many perish 

 if a spell of cold weather follows their arrival on our shores in the 

 spring ; and, like the house-martin, they are subjected to persecution 

 by sparrows. . Both the house-sparrow, the tree-sparrow and the starling 

 may be found in possession of the nesting-holes. They occupy them 

 with impunity- for sand-martins, though they combine to harry a 

 sparrow-hawk, 3 have not yet learned to chase from their midst this 

 much less formidable foe. 



1 H. A. Mocpheraon, Fauna of Ijtketand, p. 131. 

 * JfMvUlivray, History of Bird*, Hi. 002. 



