536 



PASSEEINES. 



services they render in destroying vast quantities of noxious 

 insects, not to speak of their gentle habits, mutual attachment 

 to each other, and the happy presage they bring with them 

 of spring's advent, contribute to make them welcome visitors. 

 Nevertheless there are instances where these proper sentiments 

 yield to the love of destruction where their innocent confidence 

 is rewarded by death. 



Swallows generally have the breast and belly white, and the 



Fig. 241. The Clift' Swallow (Hirundo fuiva, GUI.;. 



upper parts of the body black, tinted with a reflected blue or peach 

 colour. There are about sixty species spread over the globe, of 

 which six only are natives of Europe. They are divided into 

 Swallows proper (Hirundo), Martins (Chelidons), Sand Martins 

 (Cotyle), and Swifts (Cypselus). The Martins are larger in size 

 than the true Swallows ; have the wings longer, and consequently 



