102 'jRflfiKZU WORTH KNOWING. 



of them. The situation varies as much as the birds them- 

 selves. Trees, however, form the most common support : 

 among the tip-top branches of them warblers fix their tiny 

 cradles; to the outer drooping twigs of them orioles and 

 vireos can swing their hammocks; upon their stout horizon- 

 tal limbs the thrushes and tanagers may come and build ; 

 against the trunk, and in the great forks, hawks, and crows, 

 and jays will pile their rude structures ; and in the cracks 

 and crannies, titmice, nut -hatches, and woodpeckers clean 

 out old holes, or chisel new, in which to deposit their 

 eggs. But most of the large birds of prey inhabit lone 

 crags, making an eyrie which they repair from year to year 

 for the new r brood. The ground, too, bears the less preten- 

 tious houses of sparrows and larks, and the scattered eggs 

 of sand-pipers, gulls, and terns ; the marshes are occupied 

 by rails, herons, and ducks ; the banks of rivers are bur- 

 rowed into by kingfishers and sand-martins; so that al- 

 most every conceivable position is adopted by some bird 

 or another, and its peculiar custom usually, though not by 

 any means invariably, adhered to by that species. A curi- 

 ous instance of change in this respect is shown by the two 

 barn-swallows and the chimney-swallow, which, before the 

 civilization of this country, plastered their nests in caves, 

 and in the inside of hollow trees, as indeed they yet do in 



