CHAPTER O 



Problems of Equilibrium 



If dividing Leucophrys piriformis are treated with a 

 hypertonic solution [E. Chatton (1921)], the constriction is 

 inhibited. The proter and the opisthe may fuse in such a 

 way that the tw^o stomatogenic meridians are back to back. 

 The monster has a double set of somatic kineties, two 

 mouths, one macronucleus, and one or two micronuclei. 

 According to E. Faure-Fremiet (1948a), the stability of the 

 ^^doublet" of Leucophrys patula is bound to the mainte- 

 nance of axial symmetry. If any asymmetric phenomena 

 occur during division, if for example one mouth is lost, the 

 result will be a ciliate possessing one mouth and two sets 

 of kineties. Then, progressively, the number of kineties 

 will diminish and go back to the original number. The 

 nuclear duality, when it exists, disappears, and finally the 

 normal, original structure is obtained. 



But it happens sometimes that non-disjunction of the 

 proter and opisthe leads to heteropolar monsters, which are 

 able to feed and to grow, but not to divide, and which 

 finally cytolyse. In these heteropolar monsters, the kineties 

 diverge from two or more poles and their elongation gives 

 rise to multipolar systems. According to Faure-Fremiet, 

 there is a "geometrical impossibility" of the formation of a 

 division zone separating two systems of homogeneous and 

 homopolar kineties. It must not be forgotten that kineties, 

 according to the law of desmodexy, are dissymmetric struc- 

 tures. The kinetial system is compared by Faure-Fremiet 

 to a "crystalline network" or to the ''complex mesh of a 

 supermolecular structure of the crystalhne type." Faure- 



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