I9I9] 



HAAS—RESPIRA TION 



351 



electrical resistance of the normal tissue be called 100 per cent, it 

 is found that after killing the resistance falls to about 10 per cent. 

 When the resistance has fallen to 15 per cent the tissue is for all 

 practical purposes dead, as there is no recovery when it is returned 

 to normal conditions.^ 



The results of the experiments showing the relative amount and 

 relative rate of respiration of tissue of Laminaria when subjected 

 to various treatments are presented in tabular form. In every case 

 6-12 or more closely agreeing results were obtained and the data 



TABLE I B 

 Net electrical resistance of Laminaria in sea water 



AND IN SEA water APPROXIMATELY SATtlRATED WITH 

 ETHYL BROMIDE, EXPRESSED AS PERCENTAGE OF NET 

 RESISTANCE AT START OF EXPERIMENT AT 20° C. 



of a typical case presented. Table I A shows the relative amount 

 and relative rate of respiration as influenced by sea water approxi- 

 mately saturated with ethyl bromide. This is the only experiment 

 in which the PH value of the control differed from the PH value 

 of the sea water containing anesthetic (at the start of the experi- 

 ment). It will be noted that after about 130 minutes no respiration 

 was detected. An examination of table I B, which gives the net 

 electrical resistance of Laminaria, shows that the material can be 

 considered dead before the end of 60 minutes. From table I A 

 it is seen that at the end of 60 minutes the relative rate and relative 



3 The determinations were made in part by Professor Osterhout and in part by me. 



