354 Maternal hiheritarvce and Mendelism 



As the colour of the shell and yolk of both variants was the same, 

 we must attribute the chief cause of those characteristics to the pigment 

 of the serosa, a product of the combination of both parental gametes. 



We started our breeding experiments in the spring of 1908. 



The First Generation. 1908. Spring. 



We reared two batches of eggs from each variant. The normal 

 series gave 72 matings or batches and the brown series 87, all of which 

 were divoltine white in colour and we were unable to distinguish which 

 were normal and which were brown. This characteristic, producing un- 

 coloured eggs, is one of the normal characteristics of di-, tetra- or multi- 

 voltine breeds in Japan. In these breeds, the eg^ laid by the spring 

 brood generally produces no dark pigments in the serosa and conse- 

 quently it remains whitish until the embryo is completely developed. 

 Tropical multivoltine breeds, such as Siamese white or yellow which 

 produce 8 or 9 broods in a year, never produce any dark pigment in the 

 serosa, the colour of the egg therefore being determined by that of 

 the yolk and the shell. Sometimes it happens that certain eggs of the 

 spring brood of di- or multivoltine breeds turn into the ordinary dark 

 slate-colour, in which case most or all of them become univoltine in 

 character and do not hatch until next spring comes. On the contrary, 

 all the eggs laid by the summer or autumn broods of divoltine or other 

 multivoltine breeds deposit normal dark pigments in the serosa, thus 

 giving various colours characteristic to the respective breeds. 



The Second Generation. 1908. Summer. 



Summer broods derived from the whitish eggs of the spring broods 

 from normal and brown series yielded the antagonistic characteristics as 

 shewn below. , 



1. £!ggs laid by the Summer Broods of the Brown Series. 



Totals ... 10 30 36 76 



