the last laid. I had not the opportunity to watch which egg 

 hatched first, so took a long series of eggs for reference, which I am 

 showing together with a long series, taken at the same place in 

 1903 for the same purpose. That the odd egg is due to failure of 

 colouring matter I have very great douhts, because the odd egg is 

 almost always marked quite differently, in some cases being blotched 

 W'hile the other eggs are finely speckled, and vice versa. Although 

 the pale eggs show more of the white ground-colour, the blotch«s 

 are not weak in pigment, and are what I should call, using a photo- 

 graphic term, sharp — not washed-out or blurred. Looking at the 

 various clutches I find that what is the odd egg in one clutch is 

 the predominant one in another, and in some clutches the last and 

 odd egg is the darkest. 



"I have seen it stated that the influence of the male of a pair of 

 birds cannot afiect the colour of the egg laid by the female. What 

 I suggest, however, is that the colouring of the odd egg may be 

 affected through the male parent of the female having been hatched 

 from a clutch where pale eggs were dominant. 



"The regularity with which the odd egg occurs points rather to 

 some law at work, either Mendelian or another law somewhat 

 analogous to it, than to a mere absence of pigment. I should 

 mention that in some clutches of five there is no odd egg at all. 

 This may be caused through both the grandparents being from a 

 stock which laid pale eggs or vice versa, as I have both pale and 

 dark clutches without an odd egg. 



"On the other hand, I have clutches of six where there are two 

 odd eggs. . That the odd egg is laid by the same female and not 

 deposited by another, as I have seen suggested, is I think proved in 

 one clutch, in which all the eggs are of the same peculiar shape, 

 and in another in which all the eggs have a fault in the shell — a 

 small bump — in the same position in each egg. 



" I have a clutch of six eggs of the Linnet AcantJiis {Carduelis) 

 cannabina : five have the ground-colour white, and the sixth and 

 last egg laid has a bright blue-green ground-colour. All the eggs 

 have the markings normal. 



" I have two clutches (five and six) of eggs of the Sparrow-Hawk 

 {Accipiter 7iistts) with white ground-colour and deep brown markings, 

 with the exception of the last egg laid, which in each case has a 

 pale blue ground-colour and bright red markings. In one clutch 

 four eggs have violet underlying markings ; in the fifth and last 

 egg these are absent. 



"The odd egg, however, is not the last laid with all species. Last 



