350 A. J. Goldjarh 



Experiment JO. The stems from the preceding experiments 

 were removed from their solutions to normal sea-water. Four to 

 six days after the transfer, hydranths appeared, first, on stems 

 from the least diluted sea-water, later on stems taken from 20 

 to 30 per cent dilutions while no regeneration occurred on stems 

 kept in water diluted 40 per cent or more. The number regen- 

 erated increased daily but not to the same degree, so that by the 

 eleventh day after the transfer the stems taken from the greatly 

 diluted water regenerated as much as those taken from the normal 

 or slightly diluted sea-water. 



TABLE i3 



Stems in dilute solutions for 1 1 days were transferred to normal sea-water 



The effects of concentrated sea-water will be taken up more 

 fully in the following experiments. 



Experiment 5 J. A graded series was made by boiling and there- 

 by concentrating sea-water. For example, 200 cc. of sea-water 

 at 18° C. when boiled to a volume which at the original tempera- 

 ture was 180 cc. constituted a 90 per cent concentrated solution. 

 The water was filtered and aerated by thorough shaking. Every 

 few days the water was replaced by water freshly concentrated 

 to about the same per cent. 



