16 INTRODUCTIOX. 



are the Pewees, swallows, and those birds who lay their eggs 

 in holes. The second set of eggs usually' appears from four to 

 six weeks after the first, if that has not met with serious mis- 

 baps ; otherwise, sooner. If a hawk's nest be robbed, i3 the 

 parents commonly repair an old nest near by, often hastily 

 lining it with evergreen or the like, and at the end of about 

 a fortnight two or three eggs are laid. The Sharp-shinned 

 Hawks, Kingfishers, Golden-winged Woodpeckers, and very 

 probably other species, are said to continue sometimes for several 

 daj's to lay eggs almost daily, after the first sets have been 

 taken, though continually robbed. Smaller birds have been 

 known to build a second, and even a third nest, within a few 

 feet of the previous ones, when these were removed. 



They have also been known to cover the eggs of a Cow-bird, 

 by building a second story, or even a third, wliich became 

 their own nursery. Such cases are, however, exceptional, and 

 lead me to speak of desertion. 



§ P. Birds differ widely in respect to desertion, the wood- 

 peckers, especially the Golden-winged, being in case of disturb- 

 ance uncertain in their movements. Tlie latter often leave 

 forever the excavation, on whicli they are at work, if they 

 imagine that they are w^atched, though occasionally regardless 

 of those passing by. If their eggs be disturbed, they some- 

 times " desert," and at other times the female continues to lay 

 eggs in the manner already described. Slie often deepens her 

 nest, and lays a second set. A general rule is that birds will 

 not desert their nests (if not injured) when one egg is taken 

 from three or four, two from five or six, and three from more 

 than six. Never handle a nest or eggs, not to be at once 



13 Unless that of a Marsh (or Sparrow ?) Hawk. 



