ON THE LIFE-HISTORY OF CUCULUS CANORUS. 197 



11. Notes Oil tlie Liie-Histoiy of Cuculas canorus, with 

 exhibition of eggs. By A. H. Evans, F.Z.S. 



[ Received February 7, 1922 : Read February 7, 1922.] 



A farther paper on the Common Cuckoo might well be con- 

 sidered superfluous, if it were not for the fact that an examination 

 of the literature on the subject shews that this is by no means 

 the ease ; many of the details of the bird's life-history are found 

 still to need proof, and are merely reiterated from the pages of 

 previous authors, who in place of such proof make assertions, 

 Avhich though highly probable, require confirmation. 



The eggs now exhibited have been collected during a period of 

 more than twenty years, and give sure proof of the facts 

 pointed out below. 



Those of us who saw Mr. Edgar Chance's admirable film, which 

 was shown in this room some weeks ago, and redounded equally 

 to iiis credit and that of his photographer, were initiated into 

 the ways of an individual hen Cuckoo when depositing her eggs 

 and were given a clue to the probable number of them ; while a 

 meeting of the British Ornithologists' Chib next month is to be 

 devoted to the Cuculidse as a Family : but the present paper 

 deals neither with an individual and its idiosyncracies, nor witli 

 the whole of this world-wide Family, but with a species — our 

 British Cuckoo — and its regular habits. 



It is by no means easy to examine into the bii-d's life-history, 

 but the writer ikas had unusual good luck. In the comparatively 

 small grounds of Histon Manor, near Cambridge, he and the owner, 

 Mr. W. A. Harding, found that no fewer than five hen Cuckoos 

 would lay their eggs in a single year, and that in one case the egg- 

 was so remai-kable that recognition was instantaneous. Hardly 

 less remarkable were specimens from the Cam, most of which 

 are now exhibited by kind permission of Dr. Ticehurst and 

 Mr. Bonhote, and are used to strengthen the evidence for the 

 conclusions arrived at. 



Incidentally the abundance of hens at Histon tends to discredit 

 the theory of polyandry. 



The first series of clutches passed round shews the same hen 

 laying in the nests of the Greenfinch, Spotted Flycatcher, and 

 Pied Wagtail, and proves that she does not always choose the same 

 foster parent. The egg, in this case peculiar and unmistakable, 

 bears no resemblance to the others in the nest. Such resemblance 

 is the exception rather than the rule, except where, as in the 

 case of the Meadow-Pipit, the typical Cuckoo's egg is more or 

 less similar to that of its host, whose nests are plentiful and 

 easily found. Several examples are exhibited. 



The second series affords strong corroboration ; the Cuckoo's 

 egg, though less peculiar, is in each case undoubtedly that of 



