THE RETURN OF THE BIRDS 67 



which differed greatly in colour. More might have 

 been learned from the incident if it had been known 

 for certain whether the eggs had been laid by the 

 same or different birds. There is a general tendency 

 for the habits of animals to become hereditary as 

 the migrations of birds and it seems not unreason- 

 able that a cuckoo which has once laid its egg in the 

 nest of any particular species should continue to do 

 so, and that the young cuckoo hatched in the same 

 nest should also continue the practice in after 

 years. 



A possibility with regard to the cuckoo is that it is 

 not so destitute of maternal instinct as is generally 

 supposed, and that it occasionally hatches its own 

 eggs. It is certain that a female has been seen with 

 her breast destitute of feathers, and with young 

 cuckoos following her and clamouring to be fed. 

 Some other species of the genus nearly akin to our 

 own bird are quite normal in their nesting habits, 

 and it is here suggested that, under certain circum- 

 stances, our English cuckoo may be so likewise. 



All the cries and calls of the cuckoo are love songs 

 and are closely connected with the " pairing " 

 season. The birds begin to shout upon recruiting 

 soon after their arrival, and this continues through 

 May and until June. The couplet to the effect that 

 " The first cock of hay frights the cuckoo away," 

 holds good in the districts in which it is used ; and it 



