PAIRING. 139 



forcing the grubs and worms so deep into it as to 

 be out of reach, while, the operations of plough- 

 ing and digging having almost ceased, they have 

 little aid from the labours of man. In such cases 

 it has been remarked, that " the constant clamour 

 of the young for food, so unusual in nestling birds, 

 renders it manifest that the labours and exertions 

 of the parents cannot supply a sufficiency for their 

 requirements."* If, then, the difficulty is so consid- 

 erable when both parents conjoin their labours, it 

 may be inferred that it would, even in ordinary cir- 

 cumstances, be too much for the female alone, more 

 particularly as her energies must be somewhat im- 

 paired by the previous fatigue undergone in the 

 process of hatching. During this process the aid 

 of the male is no less indispensable than in feeding 

 the young. 



It is obvious, that while the hen has to sit for a 

 number of days in order to hatch her eggs, and can- 

 not, as we shall afterward see, leave them for many 

 minutes without incurring the risk of destroying 

 the embryo chicks, she must either run this hazard 

 or perish of hunger, unless she had food brought to 

 her. This, indeed, may be considered as almost the 

 commencement of the labours of the male bird; 

 for, though he helps a little in the building of the 

 nest, he does not work at it with the unwearied as- 

 siduity of the female. In the instance of the ca- 

 pocier (Sylvia macroura), Vaillant tells us that he 

 observed the female to be much more active and 

 anxious about the building than the male, even 

 punishing him for being frolicksome and idle by 

 pecking him with her beak ; while, in revenge, he 

 would sometimes set about pulling portions of the 

 nest to pieces. 



Independently, then, of assisting to build the nest, 

 the female evidently could not well perform her 



* Journal of a Naturalist, p. 259, 3d edition. 



