3S8 



BOTANICAL GAZETTE 



[aprtl 



drying treatment (which killed the tissue). The results are given 

 in table V A, the control data being given in table V. The rela- 

 tive amount of respiration after the treatment was very high and 

 after 2 hours was still at 3. The relative rate of respiration after 

 the treatment was very high at the start but gradually declined 



to normal in 2 hours. 



TABLE IV 



Control for IV A: 15 periods (21 min. each) in sea water; solution 



RENEWED AT BEGINNING OF EACH PERIOD 



Another method used in killing the tissue was by placing it in 

 running tap water. A preliminary determination of the electrical 

 resistance showed that 22 hours were more than sufhcient to kill 

 the tissue. The experiment was begun at 11:18 a.m. and at 

 7:50 P.M. the tissue was still somewhat ahve, but at 9:25 A.M. 

 next day the tissue had in all probability been dead for some time. 

 The respiration was then determined before and after exposure 

 to running tap water for 19 hours. The results are given in 

 table VI, the data for the control being given in table V A. In 

 table VI it is obvious that no respiration of the tissue was observable 

 after it had been in tap water for 19 hours. There is of course 

 the possibility that the rise and decHne of the respiration after 

 death was so rapid as to escape observation if the tissue had been 

 dead much before the end of 19 hours. 



