[Vol. 2 



546 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



To show the comparative effects on the exosmosis from the 

 roots of plants treated with ether, chloroform, and illuminat- 

 ing gas — both when applied as vapor and when introduced 

 into the water — the conductivity curves of fig. 12 were plotted. 

 The results, somewhat classified, are also given in table v. It 

 will be seen that the quantity of anesthetics used and the dura- 

 tion of treatment varied in individual cases. 



The indications are, therefore, that for an equal exposure 

 the vapors range in order of effectiveness as follows : ether, 

 least ; illuminating gas, more ; and chloroform, most. The dif- 

 ference in effectiveness between the ether and the chloroform 

 is especially interesting, more so when we note that 8 cc. of 

 ether were used and only 1£ cc. of chloroform. This would 

 seem to be in harmony with the findings of Graham ( '14) ; he 

 was able to produce liver necrosis by some aliphatic halogen 

 substituted compounds, but not by ether or chloral hydrate. 



As regards the fact that No. 11 (4 per cent ether, remaining 

 in the water) has a higher curve than No. 12 (10 per cent ether 

 for 30 minutes) and especially at the beginning, it should be 

 stated that in the case of Nos. 4, 6, 8, 10, 12, and 14, the treat- 

 ment was given while the roots were in distilled water plus 

 the anesthetics. Following the treatment the roots, after rins- 

 ing, were placed in distilled water, and at the end of one- 

 half hour the first reading was taken. In the case of Nos. 11 

 and 13 the water containing the anesthetic was not replaced 

 by fresh water and the first reading was taken one-half 

 hour after the treatment began. Since the exosmosis during 

 the first half hour is unusually rapid as a result of anesthetic 

 treatment, it will be seen that in replacing the medium at the 

 end of that period, the excreted material was thus discarded 

 for that interval. Hence, such curves represent a secondary 

 exosmosis. The curve of No. 11, therefore, is for total exos- 

 mosis, while that of No. 12 is for partial exosmosis. 



The condition of the cultures which furnished the results 

 plotted in fig. 11 is given for various periods in table vi. 



In fig. 13 the secondary exosmosis after the first half hour 

 is graphically represented for some organic compounds in con- 

 siderable concentration. The purpose was, of course, to use a 



