ATTENTION DURING INCUBATION. 43 



In DUCKS the duration of sitting was from twenty- 

 eight to thirty-two days. 



Common GEESE from twenty-nine to thirty-three 

 days. 



PIGEONS from seventeen to twenty days. 



There is occasionally a deception in this case. Some 

 hens sit unsteadily, or rather stand over their eggs, 

 during the first four or five days, leading ultimately 

 to the supposition that they have sate some days 

 beyond the usual period. 



