CHAPTER XIII 



RECONSTITUTION IN 

 DISARRANGED STENTORS 



CiLiATES are often cited as achieving in complexity of structure 

 and multiplicity of function the highest elaboration of the cell as 

 a unit, choosing Epidinium as the ultimate. Stentors, with their 

 elaborate feeding organelles, complex kinetics, ribbon bundles and 

 M-bands in the clear stripes, and granular bands of varying width 

 and taper such that any part of the ectoplasm is theoretically 

 identifiable with reference to its position in the orderly whole, are 

 not far behind. Yet in spite of the cogency and high development 

 of the cortical pattern, stentors can sustain and recover from drastic 

 disruptions of this exquisitely organized ectoplasmic structure. 

 Nor is reconstitution accomplished by the easier way of resorbing 

 existing cortical differentiations and starting afresh, as in Bursaria 

 truncatella in which excessive injuries lead to encystment followed 

 by complete reconstruction, according to Lund (19 17). Instead, 

 the cut up and disarranged parts of stentors largely persist as such 

 and apparently perform remarkable shifts and reorientations and 

 rejoinings in a usually highly successful recovery of the normal 

 pattern of the cell. This performance in fact suggestively parallels 

 the reconstitution by dissociated sponges and disaggregated tissue 

 cells of organized, functional units. 



I. Minced stentors 



The most drastic operation conceivable with Stentor is rather 

 easily accomplished. The ectoplasm can be cut into as many as a 

 hundred separate patches by slashing deeply through the surface 

 of the cell with the sharp point of a glass needle. After many cuts, 

 large patches will have been circumscribed and ** float " free on 

 the endoplasm. When these in turn are repeatedly transected, the 

 needle not only severs the formed structures but also pushes the 

 patches into gross disarrangements with reference to one another 



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