Bioelow. — Nuclear Cycle of Gonionemus murbachii. 



Fig. 115. Still later prophase. The nuclear membrane has broken down. Sev- 

 eral dumb-bell-shaped chromosomes have been formed by the con- 

 densation of the chromatin segments. 



Fig. 116. Metaphase ; polar view. The chromosomes are dumb-bell-shaped; 

 several of them have divided. 



Fig. 117. Late metaphase. Most of the chromosomes are in process of splitting. 



Fig. 118. Metaphase in side view. The chromosomes appear as spheroidal 

 masses. The centrosomes are now visible. 



Fig. 119. Anaphase. The chromosomes form daughter plates. Most of them 

 preserve their orientation parallel to the plane of future cell division. 

 Stout interzonal filaments connect the two daughter groups. 



Fig. 120. " Resting " stage of oocyte. The nucleolus is compound. 



Fig. 121. Early pseudoprophase of oocyte. 



Fig. 122. Pseudoprophase. Several chromatin segments have been formed by the 

 coalescence of the karyosomes. 



Fig. 123. Later stage of the same. The nucleolar shell has partly broken down. 



