396 



BOTANICAL GAZETTE 



[may 



224 min. the relative amount is about 1.5, while the relative rate 

 falls below the normal after about 130 min. The maximum 

 increased rate, when 24.2 per cent alcohol is used (figs. 4a [A] and 

 4b [A]; table IV A), is reached during the first period and then 

 becomes smaller very much more rapidly than at any of the lower 



TABLE IV A 



Two PERIODS (31 . 25 MIN. EACh) IN SEA WATER AND 6 EQUAL PERIODS IN SEA WATER 

 CONTAINING 24.2 PER CENT (bY VOLUME) OF ETHYL ALCOHOL 



Solution 



Sea water . 



u u 



Sea water containing 24 . 2 per cent 



ethyl alcohol 



Sea water containing 24 . 2 per cent 



ethyl alcohol 



Sea water containing 24 . 2 per cent 



ethyl alcohol 



Sea water containing 24 . 2 per cent 



ethyl alcohol 



Sea water containing 24.2 per cent 



ethyl alcohol 



Sea water containing 24.2 per cent 



ethyl alcohol 



Change in PH 



Relative rate of respiration 



7.90-7.43 =0.47 

 43 =0-47 



90-7 

 90 — 6 

 90 — 6 

 90-7 

 90-7 

 90-7 

 90-7 



i6* = 

 75 = 

 25 = 



= 1.74 



^115 

 = 0.65 



55 =0.35 

 80 =0.10 

 84 =0.06 



1.74-4-0.47 = 3.7 

 i.i5-=-o.47 = 2.4 

 0.65^0.47 = 1.4 



o-35-^o-47 = o.7 

 o. io-i-o.47 = o.2 

 0.06-^0.47 = 0. 1 



* Approximate (at this point the indicator is not very sensitive to changes in PH). 



TABLE IV A CONTROL 

 Eight periods (30.25 min. each) in sea water 



Period 



I. 

 2. 



3- 



4- 

 5- 

 6. 



7- 



Relative rate of respiration 



0.37-^0.37 = 1.0 

 0.37-^0.37 = 1.0 

 0.37^0.37=1.0 

 0.36-7-0.37 = 0.97 

 0.36-7-0.37=0.97 

 0.35^0.37 = 0.95 

 0.35-^0.37 = 0.95 

 0.32-^0.37 = 0.87 



concentrations, falling below the normal rate at about no min. 

 The curve for relative amount of respiration at the end of 3 hours 

 is about 1 . 4, even though respiration has nearly ceased. 



These curves, showing the effect of varying concentrations of 

 alcohol upon the rate of respiration, indicate that for concentrations 

 above i per cent there is a marked increase in the respiratory 



