INCUBATION. 219 



being constantly taken away, the bird is always 

 laying, and does not apply herself to the task of 

 incubation for a time at least. The common hen, 

 however, will sit upon only one egg, when the 

 instinct of incubation comes strongly upon her. 

 The Poland breed of hens have little or no desire 

 to incubate, and their eggs are consequently put 

 under other hens, in which this desire is uppermost 

 for the time being. Hens will sometimes sit for 

 weeks upon an empty nest. The turkey is also 

 a good incubating bird, and will sit, says Mr. Jesse, 

 for months together upon a very scanty supply of 

 food. These are circumstances which the poultry- 

 keeper pays much attention to. 



In a wild state no bird will sit upon its nest 

 when all the eggs are removed. Therefore, al- 

 though the instinct of incubation, which effects so 

 great a change in the habits of the female bird, is 

 very strong, yet it is not, in a natural state at least, 

 a blind instinct which would lead to the bird sitting 

 upon its nest, when every possibility of the appear- 

 ance of a brood of young to reward its patience 

 was at an end. In such cases either the nest 

 is abandoned, or the bird, instead of attempting 

 to incubate, will lay a new set of eggs. It is 



