400 



BOTANICAL GAZETTE 



[may 



exposure the color was almost entirely reversible, and after the 

 third period (and succeeding periods) the color was completely 

 reversible. When sea water containing 24 . 2 per cent ethyl alcohol 

 (made up to conductivity of sea water) was used, the color of the 

 indicator after the first period of exposure was not reversible. The 



TABLE IV F 



Two PERIODS (34.75 MIN. EACh) IN SEA WATER FOLLOWED BY 5 EQUAL PERIODS IN 

 SEA WATER CONTAINING I PER CENT ETHYL ALCOHOL 



Solution 

 Sea water 



u u 



Sea water containing i per cent 



ethyl alcohol 



Sea water containing i per cent 



ethyl alcohol 



Sea water containing i per cent 



ethyl alcohol 



Sea water containing i per cent 



ethyl alcohol 



Sea water containing i per cent 



ethyl alcohol 



Change in PH 



Relative rate of respiration 



65-7-40 = 0.25 



6o-/ 

 65-7 

 65-7 

 65-7 

 65-7 

 65-7 



35 = 0.30 

 35 = 0.30 

 35 = 0.30 

 35 = 0.30 

 40 = 0.25 

 43=0.22 



o.3o-=-o.275 = i.i 

 o.30-=-o.275 = i.i 

 o.30-^o.275 = I.I 

 0.25-^0.275=0.91 



O. 22-^0. 275=0.80 



TABLE IV D, E, F CONTROL 



Six PERIODS (35.5 min. each) in sea water 



color of the indicator at the end of the second period of exposure 

 was almost completely reversible, but after each subsequent period 

 the color was fully reversible. 



The reason for these instances of irreversibility can easily be 

 explained. Phenolsulphonephthalein in the acid end of its range 

 is yellow. Laminaria has a yellowish brown pigment which may 

 come out when the cells are injured by very strong concentra- 

 tions of the anesthetic, while the green pigment does not come out. 

 When the concentration of the anesthetic is so great as to rapidly 

 injure the cells (as is the case with all of the exceptions just noted) , 



