O. L. INMAN 537 



of the same specific gravity as sea water (specific gravity 1.024), of 

 sodium chloride and calcium chloride were tried; also a mixture of 

 sodium chloride and calcium chloride in the molecular proportion of 

 50:1. The results were all similar to those produced by the use of 

 hypertonic sea water on Laminaria in that there was always a fall in 

 the rate of respiration. 



SUMMARY. 



1. In highly hypertonic solutions of sea water the rate of respiration 

 of Laminaria agardhii is rapidly reduced. 



2. In highly hypotonic solutions the rate of respiration of Laminaria 

 agardhii is reduced somewhat less rapidly than in the case of hyper- 

 tonic solutions. 



3. Hypertonic solutions of NaCl, CaCl2, and of mixtures of NaCl 

 and CaCl2 in the proportion of 50: 1, all caused a decrease in the rate 

 of respiration of wheat seedlings. 



