CHAPTER i 



Order and Disorder; 

 Torsion and Detorsion 



When considering the different phases of the Ufe cycle 

 of apostomatous cihates, one is struck by the alternation of 

 spiral and meridian stages. This is especially striking in 

 Foettingeria, and thus we are naturally led to the problem 

 of torsion and asymmetry. Before discussing this problem, 

 let us say a few words concerning the kinetodesma. 



As already stated, the kinety is essentially a line of 

 kinetosomes with a kinetodesma at their right. The origin 

 of the kinetodesma is not clear. But in the trophont of 

 Foettingeria where the kinetodesma is, in some of its parts, 

 relatively large, it shows a fibrillar structure and the kineto- 

 somes seem to be in continuity with the fibers, that is to 

 say, to be attached to the kinetodesma. It is known that 

 kinetosomes of flagellates often produce fibers. It is there- 

 fore possible, and probable, that the kinetodesma represents 

 fibers of kinetosomal origin. 



Whatever its origin may be, the kinetodesma seems to 

 play an important role in morphogenesis. In the trophont 

 of the apostomatous ciliate Traumatiophtora punctata, an 

 anarchic field of kinetosomes is always present between the 

 anterior sectors of the rows 10 and 1. The row 11 starts 

 somewhat lower. Obviously, the kinetosomes of the an- 

 archic field represent the kinetosomes of the anterior sector 

 of the kinety 11. This conclusion is reinforced by the fact 

 that these kinetosomes are paired, as are always the kineto- 

 somes of the anterior sectors of the rows n and n — \ (in 

 this case n = 11). 



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