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PROTOZOOLOGY 



(Fig. 87). According to No land (1927), the conjugants fuse along the 

 anterior end (a), and the micronucleus in each individual divides in 

 the same way as was observed in Paramecium caudatum ib-e). But 

 the cytoplasm and both pronuclei of one conjugant pass into the 

 other (J), leaving the degenerating macronucleus and a small 



Fig. 86. Sexual reproduction in Vorticella microstoma, X800 (Fin- 

 ley), a, preconj ligation division which forms a macroconjugant ami a 

 microconjugant; b, a macroconjugant with three microconjugants; c, a 

 microconjugant fusing with a macroconjugant; d, the micronucleus of the 

 microconjugant divided into four nuclei; e, with 12 nuclei formed by di- 

 visions of the two micronuclei of conjugants; f, synkaryon; g, eight nu- 

 clei after three divisions of synkaryon; h, seven enlarging macronuclear 

 anlagen and a micronucleus in division; i, first division; j, a daughter in- 

 dividual with a micronucleus, four macronuclear anlagen. and old macro- 

 nuclear fragments. 



