[38] 



An unbiassed examination of these eggs and their foster clutches suggests 

 the following observations : — 



(a) There is a resemblance in coloration both as regards intensity and 

 distribution which is remarkable. 



(b) It is not surpassed nor even equalled in the coloration of the eggs 

 composing the individual clutches in which the eggs have been found. 

 There is noticeable variation in the different clutches of the same kind of 

 bird's eggs, e.g. Sedge Warbler's in this collection which contrasts with the 

 uniformity of appearance of the Cuckoo's eggs of the series. 



We have here either the eggs of two or more birds, in which case a 

 marvellous coincidence of colour resemblance extending to eleven eggs 

 occurs ; or the eggs are those of a single bird. 



If the latter alternative be correct, two facts of interest are to be noted. 

 One is the confirmation of the observations of Baldamus and others that the 

 resemblance in the eggs of the individual Cuckoo extends from one year to 

 another. The second is that a single Cuckoo may lay as many as ten eggs 

 in a season, and that within so short a period as twenty-two days.' 



Further, it will be noted there are four foster species involved; these 

 however all nest in similar situations. The actual distance limit of this 

 Cuckoo's ovipositing operations here considered was about two miles. 



VIII. — Three eggs, taken in Huntingdonshire. 



These are pale greenish eggs with brown blotching, mostly at the broad 

 end. These eggs were all taken in the same area. Three foster species are 

 involved. 



IX. — Three eggs, taken in Huntingdonshire. 



Date when taken. 

 . 26th May 1913 

 . 29th May 1913 

 . 3rd June 1913 



' Six to seven is the usual number of eggs reputed to be the product of a single Cuckoo 

 in a season. I do not know upon wliat evidence this is based, but considering the con- 

 tingencies in the matter of rearing there might well be a compensating factor in this 

 species in the direction of an increased egg production. 



