INTRODUCTION. xxin 



from a similar change. The best-fed fowl ceases at this time 

 to lay. The season of moulting is generally the end of summer 

 or autumn, and their feathers are not completely restored till 

 the spring. The male sometimes undergoes, as we have already 

 remarked, an additional moult towards the close of summer ; 

 and among many of the waders and web-footed tribes, as Sand- 

 pipers, Plovers, and Gulls, both sexes experience a moult twice 

 in the year, so that their summer and winter livery appears 

 wholly different. 



The stratagems and contrivances instinctively employed by 

 birds for their support and protection are peculiarly remark- 

 able ; in this way those which are weak are enabled to elude 

 the pursuit of the strong and rapacious. Some are even 

 screened from the attacks of their enemies by an arrangement 

 of colors assimilated to the places which they most frequent 

 for subsistence and repose : thus the Wryneck is scarcely to be 

 distinguished from the tree on which it seeks its food ; or the 

 Snipe from the soft and springy ground which it frequents. 

 The Great Plover finds its chief security in stony places, to 

 which its colors are so nicely adapted that the most exact 

 observer may be deceived. The same resort is taken advantage 

 of by the Night Hawk, Partridge, Plover, and the American 

 Quail, the young brood of which squat on the ground, instinc- 

 tively conscious of being nearly invisible, from their close 

 resemblance to the broken ground on which they lie, and trust 

 to this natural concealment. The same kind of deceptive and 

 protecting artifice is often employed by birds to conceal or 

 render the appearance of their nests ambiguous. Thus the 

 European Wren forms its nest externally of hay, if against 

 a hayrick ; covered with lichens, if the tree chosen is so 

 clad ; or made of green moss, when the decayed trunk in which 

 it is built, is thus covered ; and then, wholly closing it above, 

 leaves only a concealed entry in the side. Our Humming- 

 bird, by external patches of lichen, gives her nest the appear- 

 ance of a moss-grown knot. A similar artifice is employed by 

 our Yellow-breasted Flycatcher, or Vireo, and others. Thf 



