382 Maternal Inheritance and Mendelism 



Characteristics of this Breed. 

 From the results given by rearing through consecutive generations, 

 it was ascertained that all the v^orms were normal patterned and there 

 was no considerable difference from normal breeds, except in the colour 

 of the head and eyes. In the fourth and fifth stages, we clearly 

 observed that the head of the worm was of a light reddish brown as 

 contrasted with the normal brownish grey of normal-egged breeds. 

 The eyes, both simple and compound, were tinged with crimson. The 

 eggs when newly laid are white as is the case in normal breeds. With 

 the formation of the blastoderm, they gradually changed into a light 

 orange, then into brownish orange and at last into clear crimson. They 

 do not remain the same in colour throughout the year ; when the 

 development of the embryo is in its earlier stages they take on some 

 shade of brown which gradually merges into a clear crimson. After the 

 hibernation, when the development of the embryo again takes place in 

 spring, they assume a dark shade of crimson and the pigments are not 

 uniformly distributed in the serosa. The shell is white. The shape is 

 quite normal. The cocoons are white, and their form is cylindrical with 

 the constriction in the middle like that of the normal Japanese breed. 

 The moths are white, with faint markings as in normal light moths. 

 We shall call this breed the " Crimson-egged " breed. 



Grossing experiments with Normal Breeds. 



Reciprocal matings between the crimson-egged and many normal 

 breeds were made. Female moths derived from the spring brood of the 

 crimson breed were mated with males from tetravoltine white (Ono- 

 dahime), the extracted normal-egged breed derived from a cross between 

 Japanese white and the Chinese dark- wormed breed, and the divoltine 

 white (Renzoku). These three breeds were all true in their normal 

 egg-colour characteristic. The results of the reciprocal matings are 

 shewn below : 



A. F, Eggs. 



1. ($ normal breed x </ crimson breed.) 



Female parent 

 Tetravoltine white (Onodaliime) 



»> >i «» 



The extracted normal breed 



Divoltine white (Eenzoku) 



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