[VOL. 2 



532 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



some respects to that in the curves obtained from normal 

 plants. A distinction should be made here, however, from the 

 causal agency in this decline in conductivity and the anes- 

 thetic reversibility that Osterhout ('13) describes. The de- 

 cline in the curve indicates that the absorption of electrolytes 

 by roots occurs at a greater rate than they are excreted, for 

 both processes, absorption and excretion, are undoubtedly 

 going on and the curve represents the proportionate amounts 

 of each for any given time. Thus if A represents the excre- 

 tion and B represents the absorption, the curve declines when 

 B is greater than A, and inclines when A is greater than B. 

 Hence the curve may be represented as A — B = C, where C 

 represents the number of ions or charge-carriers in the solu- 

 tion. The tops of the treated plants showed no visible effects 

 whatever when compared with the controls. The roots of No. 

 45 were very slightly aifected, but those of Nos. 47 and 49 

 were considerably so and to about an equal degree, as shown 

 by flaccidity, root coloration, and the colored and turbid ap- 

 pearance of the medium ; the tops, however, continued normal 

 for 21 days after the treatment. Hence the metabolic proc- 

 esses no doubt proceeded unimpaired in many respects, as did 

 also transpiration. The decline of the conductivity curve 

 therefore represents merely a partial return to normal condi- 

 tions. But the higher conductivity of the medium shows 

 greater exosmosis than from the normal plants. This is due 

 to the unalterable and invariable (and not reversible) effect 

 of the anesthetic upon certain cells. Culture 50 shows in the 

 higher position of its curve, as compared with the other con- 

 trols, an effect that is no doubt due to the 2-hour exposure of 

 the roots to the air in the bell jar. 



As seen in fig. 6 no marked results followed the ether appli- 

 cation for one-half to two hours when the roots were in the 

 water during the treatment, though a slight rise is evident 

 for the culture exposed 2 hours. No visible effects were pro- 

 duced on either the tops or roots. 



Comparing the effects on plants of an ether vapor-saturated 

 atmosphere with those produced by an illuminating gas-satu- 

 rated atmosphere, it is thus seen that illuminating gas is much 



