[Vor. 5 
260 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
formations are also hydrophilous. The result is that the 
water in the cells is in a constant state of dissociation between 
the form (H20)x—X(H:20). Protoplasmie movement and the 
associated changes in cell contents are probably dependent on 
the exchanges occurring between the ‘‘hydrolated’’ colloid 
surfaces and the solution. The action of the anaesthetic in 
increased concentrations is believed to cause stoppage of 
movement by increased osmotic tension, which produces a 
balance of the attraction between the protoplasm and the 
solution. In a later communication (’11) these authors point 
out the applicability of Starling’s name of hormones, or ex- 
citants of functional activity to the anhydrophylie stimulants 
above noted, which pass through differential septa. 
From a general consideration of the foregoing survey of 
literature it is clear that the investigations on plants group 
themselves into three fairly distinct classes. In the first class 
are all those concerned with streaming, tropisms, germina- 
tion, growth, transpiration, respiration, etc., in which the ac- 
tivity noted, whether physical or chemical in nature, may be 
regarded as the ‘‘end product’’ of the etherization stimulus. 
In the second group are the studies dealing with the more im- 
mediate effect upon metabolism proper. The third comprises 
those relating to the effect on membrane permeability, upon 
which all the other phenomena undoubtedly depend. 
For the moment we are more especially concerned with 
the metabolism experiments. These have been of great in- 
terest and value, not only for the light which they throw upon 
the chemical processes going on within the plant at different 
stages of its life, but also for the impetus they furnish to 
pursue further the question of enzyme relation to stimulation 
phenomena. 
If it be granted that the activities studied in experiments 
of the first group,—those of ultimate response,—are primarily 
dependent upon the fundamental metabolic processes within 
the plant, we are led to one of two conclusions: (1) The ef- 
fect of narcotics is one solely concerned with membrane per- 
meability. All subsequent effects on metabolism are the in- 
direct results of such permeability changes. (2) The effect 
