20 COMPLETE INSTRUCTION IN 



silkworm this organ differs very much from 

 larger types of animal life. In the silk-miller it 

 consists of long, slender membranous tubes, fold- 

 ing and enfolding longitudinally in the body of 

 the female miller. In dissecting the insects, 

 these tubes may be stretched out so that the eggs 

 appear like strings of the smallest pearls inside 

 the tubes. 



When the male and female millers are coupled, 

 the vitalizing substance passes up these tubes 

 and fertilizes the eggs. In the body of the 

 female miller there is a strong ligament passing 

 down the body to the extreme end. When she 

 deposits her eggs, this ligament extends into 

 sight, and on either side appears an egg, which 

 she carefully deposits, and attaches to the ma- 

 terial on which she lays; then she in like manner 

 deposits from the other side, and so on, till all 

 her store of eggs has been expelled from the 

 body. Here I hold that sex is distinctly and 

 separately deposited, having been previously 

 determined in the body of the male. There 

 must be a beginning of the sex, and when once 

 begun, it never can be changed by human action 

 or invention. 



It is quite possible that a more careful appli- 

 cation of the X rays may give more light on this 

 subject. 



