38 



THE ARCHITECTURE OF BIRDS. 



around the neck of a bottle. The species arrive in 

 the west, from the south, early in April, and imme- 

 diately begin to construct their symmetrical nests, 

 which are perfected by their united and industrious 

 efforts. At the dawn of day they commence their 

 labours by collecting the necessary mud from the 

 borders of the rivers and ponds adjacent, and they 

 persevere in their work until near midday, when 

 they relinquish it for some hours, and amuse them- 

 selves by sporting in the air, pursuing insects, &c. 

 As soon as the nest acquires the requisite firmness, 

 it is completed, and the female begins to deposite her 

 eggs, four in number, which are white spotted with 

 dusky brown. The nests are extremely friable, and 

 will readily crumble to pieces ; they are assembled 

 in communities, as represented in the engraving. 



Nest of the Cliff Swallow (Hirundo fulva, VlEILLOT). 



In unsettled countries, these birds select a sheltered 

 situation, under a projecting ledge of rock; but in 

 civilized districts, they have already evinced a pre- 



