BEHAVIOR AND FUNCTIONS OF THE NUCLEUS 283 



distribution of the macronucleus. Several of these forms have 

 already been described by Stolte (1922). He associated chains 

 having noticeably recurved ends with interdivisional addition of 

 new nodes ; and he observed that in stentors with double, parallel 



Fig. 78. Location of the macronucleus in S. coeruleus. 



A. Normal location, with post-oral row, right anterior wing, 



and recurved terminal chain. 



B. Atypical macronuclear arrangements appearing autono- 

 mously, including (a) secondary row, (b) forked chain, (c) 

 coiling and posterior shift, (d) scattered nodes (whether con- 

 nected was not determined), and (e) "situs inversus" in animals 



of reversed asymmetry. 



C. Divider with 13 nodes and posterior end excised produced 

 proter with 17 small nodes in normal location and opisthe with 



13 in a ring, later becoming liistributed normally. 



D. Doublet produced by engrafting an extra primordium 

 site (without nucleus) in time develops double macronuclear 

 chain, each deployed normally with respect to the stripe pattern. 



E. When such a doublet reverts to single form the macro- 



nuclear chain becomes single correspondingly. 



