POLARITY 



A. 



into 



B. 

 C. 



G 



Fig. 53. Adjustments correcting heteropolarity. 

 When primordium site is implanted transversely it rotates 

 harmony with axis of the host, striping of the latter 



accommodating. 

 Left half rotated 180° on right, but parts eventually come 



into homopolar alignment. 

 Same operation performed on doublet stentor leads to 

 homopolar alignment of the two individualities. 



D. Fine-line zone grafted heteropolar into host with mouth- 

 parts removed. In this case regeneration anlage formed only at 

 the host primordium site, possibly because the reversed patch 



was gradually resorbed in situ. 



E. Wide-stripe sector implanted heteropolar often shifts 

 forward or posteriorly, being resorbed or isolating itself from 



the host pattern. 



F. Early primordium may fail to develop even when grafted 

 to a regenerator in same stage of development if implanted 



heteropolar. 



G. Alternatively, both early primordia may be resorbed but 

 when re-formation occurs there is no anlage induced in the 



reversed primordium site. 



H. Reversed primordium-site sector commonly leads to 



formation of three individualities, the lowest in the figure 



being of reversed asymmetry. (In part after Tartar, 1956b, 



1957c, 1958b.) 



