THE ORGANIC CELL 
25 
ment, but die. They must be regarded as merely rudimentary 
eggs, which have forfeited their right to live, for the common 
good of the permanent ovum. 
The case described below is that of Ascaris, the facts having 
been made out by Van Beneden and Boveri. 
Diagrams Illustrating the Maturation of the Egg. The 
Somatic Number of Chromosomes is supposed to be Four. 
A. Initial phase ; two tetrads have been formed in the germinal vesicle 
B. The two tetrads have been drawn up about the spindle to form the equatorial 
plate of the first polar mitotic figure. C. The mitotic figure has rotated into 
position, leaving the remains of the germinal vesicle at ij.v. D. Formation 
of the first polar body, each tetrad divides into two dyads. E. First polar 
body formed ; two dyads in it, and two in the egg. F. Preparation for the 
second division. G. Second polar body forming, and the first dividing ; each 
dyad divides into two single chromosomes. H. Final result ; three polar bodies, 
and the egg-nucleus ( ^ ), each containing two single chromosomes (half the 
somatic number ) ; c. the egg-centrosome which now disappears. 
As the egg gets ready for the formation of the first polar 
body, the chromatin in the germinal vesicle (nucleus of ovum) 
