aa THE USEFUL BIRDS 



as the following instance shows : — On the side of a certain 

 road a pair of Wood-Swallows had bnilt their nest in a young 

 elm tree enclosed in a tree-guard. This nest was removed 

 bodily in order to prevent such damage to the tree as might 

 arise from the investigations of curious boys. Undeterred by 

 this rebuff, the birds again built on the same spot, only to 

 meet with a like fate. For no less than seven times did they 

 persist in their work, evidently convinced that the fork chosen 

 as the site for their home was a desirable one, not to be 

 vacated because of such slight mishaps as the bodily removal 

 of the nest six times in succession — due, probably they 

 thought, to natural causes. After the seventh time, however, 

 they made no further attempt to build on the ill-fated elm, 

 and moved away to pastures new. 



Nest. — Similar to preceding species. Several nests may be 

 placed in orchards. 



Eggs. — Similar to preceding species, though varying greatly. 

 Obsolete marks of greyish-brown appear as if beneath the 

 surface. 



