388 



Maternal Inheritance and MendeUsm 



Greater Death-rate of the Crimson- coloured Egg. 



During our experiments with the crimson breeds, either with the 

 original divoltine or other extracted forms from cross-bred or mixed 

 breeds, it has struck us that the number of worms which came out in 

 spring from these eggs was very small, sometimes over 90 °/„ were found 

 to be dead ; even in the case where the crimson eggs were found mixed 

 with normal ones in the same batch, the mortality is much greater than 

 that of the normal-coloured eggs. We give here certain figures of the 

 death-rate observed in the crimson-coloured eggs laid by some breeds. 



Fifteen batches selected at random from 84 crimson-coloured batches 

 laid by the summer brood of the extracted crimson form, from the cross 

 between the divoltine crimson and tetravoltine normal-coloured " Ono- 

 dahime," gave the following figures : 



Totals 



5434 



4568 



84% 



The average death-rate was 84'/^, ranging from 40"8 7o to 98 7o ii 

 each batch. In 42 batches of eggs derived from the same breed, we 

 have counted 1.5,194 eggs, of which 12,796 eggs were found dead in the 

 sjjring; i.e. a death-rate of 84 "Z^^. 



In the eggs laid by a cross-bred crimson form (a cross between 

 an extracted crimson from the cross, " Divoltine crimson x Divoltine 

 Chiyodzuru," and the crimson derived from the divoltine " Tamanashi ") 

 a considerably smaller percentage of dead eggs was noted than in the 

 cross between divoltine crimson and tetravoltine white. 



