ANALYSIS OF STENTOR 255 



Stage 4 and remained as such. All these effects are quite like those 

 obtained with acriflavin by Weisz (1955). Dilute sea water also 

 produced cases of aborted fission without separation of the daughter 

 cells, as well as ectoplasmic lesions which produced a sort of 

 self-mincing in which the ectoplasmic striping was broken up into 

 irregular patches (Fig. 71 a). 



Fig. 71. 



A. Effects of sub-lethal dilutions of sea water on S. coeruleus. 

 a: Reversible inhibition (or delay) of regeneration, b: Arrest 

 of primordium development at stage 4. c: Incomplete stomato- 

 genesis. d: Incomplete division, e: Astomatous regeneration 



and breaking of stripe pattern into disorganized patches. 



B. Reactions to sub-lethal concentrations of lithium chloride 

 include the above, as well as (a) a more exaggerated self-mincing 

 of the stripe pattern with corresponding abnormality of cell- 

 shape, (b) stacking up of oral sets due to resorption failure in 

 repeated reorganizations, and (c) extraordinary increase in 

 breadth of the cell from hypertrophy of striping, leading to 

 spontaneous formation of self-reproducing doublets. (After 



Tartar, 1957a.) 



Lithium chloride in concentrations of o-i to 0-005% g^^^ 

 reversible effects which were especially interesting (Fig. 71B). 

 Again, primordium formation could be reversibly inhibited for 



