No. 612] MYXOSPORIDIAN LIFE CYCLE 



731 



are strictly opposed to all the views which maintain that a 

 copulation or so-called syncaryon formation precedes 

 spore formation. But they are all in accord with the in- 

 vestigations of all authors who have shown that there is 

 no sjTicaryon formation, but merely a plasmogamy of 

 two cells, without any copulation, at the onset of spore 

 formation. 



"\¥hen I wrote the second part of my investigations on 

 Chloromyxum leydigi, 1913, I pointed out that the facts 

 which were presented by Auerbach, Mercier and Parisi, 

 as proofs of the occurrence of a syncaryon formation just 

 before the onset of spore formation, are not quite con- 

 vincing. Their figures can easily be arranged in such a 

 manner that the supposed syncaryon formation represents 

 the division of gametocytes into a smaller cell, which in 

 m.ost all other known cases forms the membrane of the 

 pansporoblast. ( Compare Erdmann, 1917.) It is not nec- 

 essary to repeat here the attempted revision and rear- 

 rangement of the figures of these authors. This same 

 holds true for the syncaryon formation in Myxidium ber- 

 gense, Type II (Auerbach) and Oeratomyxa drepano- 

 psettcd (Awerinzew). We will take it for granted that our 

 views are correct as long as no new facts ascertained on 

 smears— not sections— compel us to change our opinion. 



As mentioned above, all authors who have shown that 

 no syncaryon formation occurs, but that a plasmogamy of 

 two cells without any nuclear fusion occurs at the onset of 

 spore formation, can agree with us that the sexual proc- 

 ess is going on at the beginning of the new life cycle. 

 Auerbach and Parisi do not convince us that the figures 

 which represent the so-called caryogamy can not be con- 

 sidered as the dividing of the gametocyte in the two cells. 

 In accordance with the facts and interpretations, Keys- 

 selitz, Schroeder, Lo Giudice, Erdmann, and Georgevitch 

 uphold the view that no merging of two cells or two cell 

 pairs takes place to form the couples of cells which are 

 later considerd as a quadruple group of the growing spore. 

 By comparing the series of figures of all those drawings 



