250 THE STORY OF THE BIRDS 



forth, just as our own Long-tailed Tit and 

 Chaffinch are in the habit of doing. The Hum- 

 ming-Birds seem very much attached to certain 

 nesting-places, often returning to them each 

 season, and they have been known to make a 

 new nest on the remains of the old ones for 

 several years in succession. 



We now come to a consideration of the various 

 types of nests peculiar to the Passeriformes. 

 This order 4 is divisible into a very large number 

 of families, but the nests in each are by no 

 means confined to certain types, and the vari- 

 ation in their structure is by no means correlated 

 with affinity. Indeed, it is by no means unusual 

 to find several very distinct types of nest in a 

 single family or even in the same genus, whilst 

 in other cases a certain type of nest will run 

 through more or less distantly related groups. 

 The variety in the nests of the Passeres can only 

 be described as amazing, and must be taken as an 

 indication of the high degree of specialisation to 

 which the order has attained, of their wonderful 

 intelligence and power of adapting themselves 

 to a multitude of conditions and circumstances. 

 We have many remarkable instances of this 

 variation of nest-type even amongst familiar 

 British species. Take the Corvidae or Crows 



