Fig. AL. Conjugation in Ajjoplophrya branchiarwn from Collin (1909), 



redrawn. 



1, "candelabra" stage of micronuclei; 2, metaphase of second pregametic micro- 

 nuclear division, macronuclei elongating; 3, prophase of third pregametic nuclear 

 division, three nuclei degenerating in each conjuganf, 4, pronuclei before exchange; 

 5, prophase of division of syncaryon, one macronucleus projecting into other con- 

 jugant; 6, telophase of division of syncaryon; 7, second postzygotic division, elon- 

 gated macronuclei stretching through both conjugants; 8, constriction of ma- 

 cronuclei, telophase of second postzygotic division; 9, exconjugant with old 

 half-macronuclei, three small nuclei, one enlarging to become an anlage; 10, exconju- 

 gant with rounded-up macronuclcar remnants, one macronucleus and one micronu- 

 cleus. 



241 



