WINGED ROBBERS AND NEST-BUILDERS. 1 55 



martin (^Qotile riparia): "a twitterer or prattler 

 by the banks of streams." As has been already 

 stated, the swallows, with a few exceptions, are 

 masons and cementers, but here is a little artisan 

 that has taken to the ways of the miners, and digs 

 a tunnel sometimes of an extraordinary length, 

 in the sand banks, at the end of which it forms an 

 oven-like apartment for the eggs. What has caused 

 this species to depart from the usual swallow- 

 method of nest building? 



Ages ago, under peculiar circumstances, it is 

 probable that the bird discovered that picking was 

 better for it than plastering; so here it is at the 

 present time with trade well learned. How hard 

 it works ! It seems impossible that such a short, 

 small beak and slender claws could perforate the 

 solid, sandy bluffs at such remarkable depths as 

 these bu'ds have been known to reach. There are 

 recorded tunnels nine feet long, although the usual 

 length is not much over two feet. The reason of 

 this great difference in the length of burrows made 

 by the same species is, that whenever they dig in 

 pebbly embankments they often in the passage 

 come upon small stones ; these, the sagacious miner 

 considers, should it locate its nest near them, would 

 prove disastrous if by accident they should fall on 



