ALCOHOLS AND FATIGUE PROCESSES 
163 
processes in plants and animals, and developmental processes de- 
pendent on growth and cell division. It is of especial signifi- 
cance to note that processes depending upon growth and develop- 
ment are included in the list, and when anaesthesia is induced 
during proper progressive developmental stages, far-reaching con- 
sequences may result. Thus abnormalities of growth and de- 
velopment as well as changes in irritability may be produced un- 
der the influence of anaesthesia as Stockard® and McClendon^ have 
shown in the production of cyclopia in developing fish eggs, and 
other developmental defects produced by alcohol in the case of 
mammals as later shown by Stockard. 
It is beyond the scope and purpose of this brief introductory 
review of facts concerned with responses of the vital processes 
to attempt to discuss the cause or causes of observed phenomena, 
but it seems logical to infer that like manifestations of ordinary 
stimulation, they are in some way intimately dependent on sur- 
face-changes of the plasma-membrane. The question as to just 
how these surface-changes are effected is a critical one, and one 
that needs more careful research. A quotation from Lillie®, on 
the theory of anaesthesia (p. 3.65) is relevant to the point just 
here. “An irritable element like a nerve-fiber or muscle-cell 
responds to a slight local electrical stimulation or mechanical im- 
pact; this response is apparently associated with a rapid and re- 
versible increase of membrane-permeability; to this latter change 
the electrical variation is apparently due. It is this membrane- 
change, with the associated variation of electrical polarization, 
which appears to be the primary physiological event of stimula- 
tion; it spreads rapidly over the whole membrane, and the other 
consequences of stimulation (contraction, increased oxidation, 
etc.) follow upon this surface change. The question thus in- 
volves the whole problem of the physiology of stimulation.- - 
The whole process of stimulation depends on the local initiation 
of the excitation state, and on the rapid conduction of this state, 
from the point of stimulation so as to affect the entire element. 
All of these processes depend on the physical and chemical con- 
dition of the membrane; hence altering this condition alters the 
whole stimulation process.” 
According to this conception the sensitivity of the membrane 
to changes of electrical polarization is its most characteristic pe- 
culiarity. The basis of this sensitivity remains to be determined. 
It would appear that the peculiar properties of the membrane de- 
pend upon its being a living structure, the seat of specific metabo- 
