WILD LIFE OF ORCHARD AND FIELD 



construction of their homes, but sometimes, like 

 other species, they alight in great flocks on the 

 reeds by the river-side and on the beach. 



The secret of the local distribution of the bank- 

 swallows lies in the presence or absence of vertical 

 exposures of soil suitable for them to penetrate 

 for the burrows at the inner end of which the nest 

 is placed. Firm sand, with no admixture of peb- 

 bles, is preferred, and in such an exposure, be it 

 sea-shore, river-bank, sand-pit, or railway cutting, 

 the face will often be fairly honey-combed with 

 burrows, so that we can readily believe that Mr. 

 Dall counted over seven hundred holes in one bluff 

 in Alaska. These are usually very close together, 

 and the wonder is how the birds can distinguish 

 their own doors. If mistakes do occur, I imagine 

 they are all very polite about it, for I know of no 

 more peaceable neighbors among birds than they. 

 The mode in which this perforation is performed, 

 requiring an amount of labor rare with animals, 

 is well described by Mr. Rennie in his Architect- 

 ure of Birds : 



''The beak is hard and sharp, and admirably 

 adapted for digging; it is small, we admit, but its 

 shortness adds to its strength, and the bird works 

 . , , with its bill shut. This fact our readers may 



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