PAIRING. J57 



beside or upon the edge of the nest. That may have 

 been one of the reasons why the one bird was said to 

 watch by the nest, while the other went to forage for 

 twigs. No female bird sits on the nest until the whole 

 of the eggs that are for one brood have been laid : at 

 least, if there be any sitting before then, it is partial, 

 and intended only to protect them from inclement wea- 

 ther. A good deal of the cawing is the noise of these 

 females. They are fed by the males from the time 

 that they begin to perch, and continually till the young 

 can live without the heat of their mother. They have 

 several calls which, by being blended together by the 

 different individuals in the rookery, produce the har- 

 mony. In cases where the male has to go to a greater 

 distance, or is less successful in rinding a supply, his 

 mate becomes clamorous for his return ; and though 

 she does not leave the tree, or even the close vicinity 

 of the nest, she hops restlessly about, and utters an 

 impatient cry. When the male comes with the supply 

 of food, the cry alters a little, the caw is shorter and 

 not so loud, but it is more expressive of eagerness. At 

 that time there can, of course, be no cawing on the 

 part of the male, which glides towards the nest with all 

 the haste that he can, and is received by his mate with 

 raised wings and open bill. The feeding is accompa- 

 nied only by a few short calls ; but when it is over, 

 the male gets a song of thanks from the female, bearing 

 some proportion, in length, to the abundance that he 

 has brought, and he rests and listens ; and the same 

 song cheers his departure when he again takes wing. 

 When the males are for some time about the nest, they 

 add to the clamour, which is carried on during the 



