WHEN THE SWALLOWS 135 



generally early in flocking, but inclined to linger as 

 long as food is abundant. Metallic blue-green above 

 and pure white beneath, the white and colour meeting 

 at a distinct line from the bill — this Swallow is 

 readily distinguished and always admired. The Cliff 

 Swallows are less familiar and seem to be decreasing 

 in numbers. They have the mud-building habits 

 and also the metallic blue-green plumage of the 

 Barn Swallows. Reddish patches on the neck and 

 above the tail are marks of identification. The big 

 Black Swallow or Purple Martin is also becoming less 

 common, and is said to show a growing inclination 

 toward passing the summer in its southern home. 

 The gathering of the flocks is a reminder of the passing 

 of summer. Even in the oppressive and close evenings 

 their chattering and crowding announce the distant 

 approach of the frost king from the north. They will 

 not wait for his blighting touch, but will seek the 

 freedom of perpetual summer before the first chill of 

 his approach. 



