364 Maternal Inheritance and Mendelisni 



Series 4. The Spindle-shaped Eggs (Fig. 13). 



In the early spring of 1909, we obtained half a batch of the eggs 

 laid by a Japanese normal univoltiue white. The egg is long and 

 spindle-shaped, and is slightly pointed at both ends. There is no 

 depression in the middle which is a characteristic common to normal 

 silk-worm eggs. 



The first generation which was reared in the spring of 1909 gave 

 eggs which were quite normal in shape and other characteristics. The 

 egg-batches obtained were only six in number. 



The second generation derived from the normal eggs yielded moths 

 which paired inter se deposited 46 batches of eggs in which we found 

 both normal and spindle-shaped ones, the number found in each mating 

 being as follows : 



Totals 33 13 46 



Of 46 batches derived from two normal matings, 13 were spindle- 

 shaped and 33 normal-shaped batches, no mixed ones. 



In the third generation which was reared in the spring of 1911, 

 both normal and spindle-shaped eggs gave moths which, when inbred, 

 laid two kinds of eggs, normal and spindle-shaped ; the respective 

 figures obtained in each mating are shewn below : 



Eggs laid 



Owing to the great havoc made by " flacherie," the mortality of 

 worms was so great that we only obtained a small number of moths, 

 yet we are able to prove that both characteristics even when inbred 

 again produce the antagonistic characteristic. Thus the order of 

 inheritance of these characteristics may be represented as below : 



