Plate VII 



e f g 



Semi-diagrammatic figures of maturation of egg of Cyclops, from RUCKERT. 

 a: Early prophase of nucleus, long double threads, b. Late prophase, threads 

 shorten and thicken, c. First appearance of spindle : the chromosomes have 

 become tetrads by a transverse break, d. Metaphase, first polar mitosis. 

 e. Anaphase. f. Prophase of second polar mitosis the chromosomes appear 

 as dyads, g. Second polar spindle dyads dividing into univalents. 



